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Fostering Communication and Collaboration
The nihCatalyst A Publication for NIH Intramural Scientists
National Institutes of Health Office of the Director Volume 15 Issue 6 November-Dece.mber i , 2007
Research Festival Research Festival of Age: Getting to the Bottom Coming Tissue Engineering and Regenerative Medicine Of the Beta Cell
by Fran Pollner by Julie Wallace
or some, the quest is to increase the progenitor pool of pancre- anel chair Rocky F atic beta cells, to derive stem Tuan noted that cells that can be controlled in cul- P this was the NIH ture and serve as replacements for Research Festival’s damaged or lost beta cells; for oth- first dedicated sympo- ers, the quest is for new treatments. sium on tissue engi- neering and regenera- Stem Cell Studies tive medicine, a re- Typically, cul- flection that the field tured human beta is steadily approach- cells do not prolif- ing the threshold of erate well or retain clinical application. the mature pheno- Indeed, applying type, noted Marvin biological and engi- neering principles to Gershengorn, chief Fran Pollner The Re-Generation: (left to right): Pamela Robey, N1DCR; of the Clinical En- Marvin repairing and replac- Cynthia Dunbar, NHLB1; Catherine Kuo, NIAMS; and panel docrinology Branch Gershengorn ing damaged and de- chair Rocky Tuan, NIAMS and scientific director, NIDDK, who stroyed tissues has at- has been exploring the optimization tracted researchers across NIH; scientists adipocytes, and chondrocytes derived of hIPCs (human islet cell-derived from three institutes described their on- from MSCs could indeed be made to precursor cells) for about five years. going research involving adult stem cell- switch identities. This capacity to de-dif- Gershengorn’s lab has established based approaches to tissue regeneration. ferentiate generated the hypothesis that that hIPCs are a special type of mes- there might be “sternness” genes that enchymal stromal cells that can be Tuan: Creating the Matrix regulate MSC self-renewal and multi- induced to differentiate into Adult stem cells and nanomaterials are potency. adipocytes, chondrocytes, and osteo- Tuan’s basic building blocks in his quest Using microarray analysis, Tuan and cytes, as well as cells of the endo- to regenerate skeletal tissues. Encourag- his colleagues determined that differen- crine pancreas. “We can change the ing results thus far in repairing joint de- tiation genes were upregulated in dif- culture conditions that result in epi- generation in rabbits foretell the appli- ferentiation and downregulated during thelial or endocrine-like cell clusters; cation of his team’s techniques to the continued on page 4 we can upregulate the insulin tran- treatment of patients with musculoskel- CONTENTS script level, generating clusters of C etal diseases such as osteoarthritis. 1 peptide-expressing cells,” he said, With the right scaffold and physical RESEARCH FESTIVAL The Eyes Have It noting that his team has transplanted and chemical environments, a cartilage Regeneration Sweat Secrets these cells into mice and demon- micromass could be developed from The Beta Cell Job Fair strated in vivo human mesenchymal stem cells (MSCs) hIPC functionality. 12-13 The lab of Sushil Rane, of the Re- to replace the degraded tissue, said Tuan, From the DDIR: Chem Informationists generative Biology Section in the chief of the Cartilage Biology and Or- Trans-NIH Initiatives: Why? How? When? 14-15 NIDDK Diabetes Branch, has been thopaedics Branch, NIAMS. The chal- GraduateStudent examining the role of the cell-cycle lenge is to generate a cartilage construct ResearchFestival/ regulator CDK4 in beta cell regen- of sufficient size to transplant into a hu- Solicitations: On Tenure Track eration. man joint, he said. Biomarkers/Speakers 16-19 Tuan’s lab evaluated whether differ- Hyperglycemic and hypoinsulin- 6-11 Recently Tenured/ emic, CDK4-knockout mice have entiated MSCs could transdifferentiate RESEARCH FESTIVAL Demystifying Agenda Chemistry Lessons clearly lost beta cell mass, Rane said; change from one differentiated state to Chromosomes, 20 continued on page 5 another. The team found that osteoblasts, SNPs, and Disease CFC Kickoff Kicks It The NIH Catalyst From the Deputy Director for Intramural Research
Trans-NIH Intramural Scientific Initiatives: Why? How? When?
ast year, with the encouragement of NIH Direc- ratories and core facilities to facilitate complete tor Elias Zerhouni, the NIH intramural research phenotyping of the human immune system and ab- L program (IRP) set out to identify important sci- normalities in autoimmune diseases and in inflamma- entific initiatives that would be difficult for any one tory processes that underlie or affect common dis- institute to support, that would exploit the special eases like cancer, asthma, and heart disease. Most of characteristics of the IRP, and would scientifically draw the studies will involve the NIH clinical center and from and benefit multiple NIH institutes and centers. human subjects. After a series of meetings involving many of our Richard Leapman, scientific director of the new principal investigators and scientific leadership, we National Institute for Bioimaging and Bioengineering, settled on three major initiatives with cross-cutting will lead an effort to develop new imaging technolo- impact: (1) Immunology, Autoimmunity, and Inflam- gies for studying molecules and cells, beginning with mation, (2) Molecular Imaging from Molecules to Cells, a center in which senior fellows from physics, com- and (3) Systems Biology. putational biology, and engineering can interact with For nearly a year, groups have met to define the NIH biologists to address the need for higher resolu- nature of each of these initiatives and how to bring tion, real-time molecular-imaging technologies. them to fruition. The resulting consensus proposals The Systems Biology proposal is the least advanced on how to proceed were then presented to me and to of the three. The proposal involves recruitment into Dr. Zerhouni—and, on October 22, 2007, to a larger leadership positions as well as the creation of an in- group of NIH scientists and scientific leadership at a cubator space for interaction of current and newly retreat held for this purpose. recruited NIH scientists. Most of us appreciate that systems approaches will begin to replace the more Why? reductionist approaches we have taken in our labora- Discussion at this retreat focused not only on the tory and clinical studies, but how this necessary evo- substance of the proposals, but also on the rationale lution will occur is still unclear. for this new approach to science at NIH. In the past, virtually all of our scientific initiatives have been in- When? vestigator-initiated or have sprung from programmatic Both the scientific community and the NIH director imperatives of the institutes (for example, the Vaccine expressed frustration at the October 22 retreat about
Research Center). This worked well for the IRP dur- why it has taken so long to get these initiatives off the ing the time of continuously rising budgets (real in- ground—although we all realize that achieving true creases adjusted for inflation of approximately 2 per- consensus among the working groups takes time. cent per year from 1980 to 2000) when new funding With nearly every square foot of space on the NIH was available to each institute or center to create a campus currently occupied with active laboratory and venture capital fund for high-risk, high-impact novel clinical science, finding appropriate space to initiate science, or even through the development of new these programs has not been a trivial undertaking. intramural programs (such as the NHGRI IRP). But we have recently figured out how to reorganize Even so, the IRP failed to be at the cutting edge of existing space to some advantage. With budgets tight some new technologies and/or model systems—such everywhere, funding was hard to find, especially be- as yeast genetics to study cell biology, and RNAi— fore goals and programmatic needs were clearly de- until they were well established in academia or in fined. To jumpstart these three projects, the NIH di- industry. Now with real budgets dropping in the IRP rector has provided $4 million from his Discretionary
for the past four years, it has become increasingly Fund for equipment needed in the instrument cores. difficult to initiate large-scale new scientific initiatives, Individual institutes and centers are expected to sup- and the need for trans-NIH cooperation and planning port the modest needs of these programs, at least dur- has become obvious. ing a period of evaluation, but most support will be in Some of the larger institutes have had the flexibility kind as the centers that are established reach out to to provide core support for expensive new technolo- the affiliate members in various institutes and centers. gies (such as transgenic mice, microarray facilities, The NIH director will meet with the scientific direc- biostatistical support, and clinical research infrastruc- tors to discuss fostering implementation of these cen- ture), but the smaller institutes have definitely been ters. We fully expect the Center for Human Immunol- disadvantaged. ogy and the Molecular Imaging Center to be function- All of these factors, plus the obvious observation ing in calendar year 2008, and the Systems Biology that working collaboratively across NIH will increase initiative will soon begin to identify leadership. creative input and reduce inefficiency and duplica- Getting NIH scientists and scientific leadership to- tion, led to the trans-NIH initiatives concept. gether to discuss these ideas has been a new and rewarding experience in itself. We anticipate a con- How? tinuing dialog between scientific leadership and sci- The original three proposals listed above were spe- entists on how to ensure that the NIH IRP remains a cifically chosen because they could provide infrastruc- vital, creative contributor to biomedical research. Com- ture for the work of many different scientists through- mitted to this objective, the NIH director has proposed out NIH and had the potential to revolutionize how a Grand Challenge program that provides one-time we do science. funding to launch innovative science that might oth- Neal Young, chief of the Hematology Branch, erwise not be initiated. Novel scientific ideas will be NHLBI, will lead the Immunology initiative. He pro- sought. As the existing trans-NIH initiatives transition posed a Center for Human Immunology, which will to more stable footing, the transitioning of leadership occupy physically proximate space for common labo- is also underway. 2 — . Novhmber-December 2007
From the Consortium Biomarkers: A Call for Ideas
he Biomarkers Consortium, a pub- tagged glucose uptake by tumors. in developing and submitting project lic-private biomedical research The Biomarkers Consortium has raised concepts and plans and generally help Tpartnership managed by the Foun- more than $6 million in private funds for keep the process on track. Barbara dation for the NIH (FNIH), provides an two NCI-led projects on lung cancer and Mittleman is the PPP program director, opportunity for intramural research staff lymphoma involving fluorodeoxyglucose and Shawnmarie Mayrand-Chung is the to engage in joint projects with indus- positron emission tomography. Another NIH program director for the Biomarker try, FDA, and a variety of other part- NIH-led project, submitted by NIMF1 in- Consortium. ners to discover, develop, and qualify tramural scientists, focuses on PET radiop- All the players have something to gain biomarkers across the spectrum of bio- harmaceutical development for neurode- from this new research opportunity, says medical research. generative and possibly atherosclerosis Consortium Director C. Anthony Altar of The Consortium is soliciting project and brain cancer therapeutics. the FNIH. Researchers secure funding concepts from researchers and the gen- Projects on imaging and biochemical for important basic research; private eral public worldwide. The Consor- markers for Alzheimer’s disease progres- companies can share the cost of research tium’s goal is to accelerate the delivery sion and on adiponectin, a candidate they otherwise would have had to fund of successful new technologies, medi- marker for diabetes, are also being con- independently; the FDA gets involved cines, and therapies. sidered. early in the drug- or technology-devel- Tried-and-true biomarkers—such as The Consortium has four subject-fo- opment process; measurements are stan- blood pressure and cholesterol levels cused steering committees at this time: dardized; and eveiyone is on the same to assess heart disease risk, and CD4 T- neuroscience, metabolic disorders, can- page. cell counts and viral-load levels to as- cer, and inflammation and immunity. Fu- Participants in the Consortium are its sess FIIV/AIDS—are windows into dis- ture steering committees can be estab- founding members—FNIH, NIH, FDA, ease progression and regression. lished as project concepts are proposed. and the Pharmaceutical Research and Biomarkers can help identify those at NIHers must submit proposed project Manufacturers of America—and more risk for developing disease, help stratify concepts through their scientific director, than 40 companies, trade associations, patients according to prognosis, dem- using the form found at the website: and advocacy groups. David Lee, deputy onstrate early signs of organ involve-
From FELCOM WALS: A Call for Speakers and nominate that person. FELCOM nominations for the 2008-2009 WALS series are now underway and will con- he NIFI Director’s Wednesday Afternoon Lecture Se tinue until November 21. ries (WALS) features top biomedical researchers from E-mail your nominations to Kristi Muldoon Jacobs T around the globe. The Director’s series has been bring- serving as a WALS host, and perhaps having breakfast with communictns/lecture-info . htm> him or her, is an excellent way to become acquainted with Finally, don’t forget the Cultural Lecture slot—do you have an admired scientist—perhaps a future colleague. a favorite writer or some other fascinating figure whose wit FELCOM is collecting nominations from the NIH fellows and wisdom you would love to bring to NIH? Think about community. So think about a speaker you have seen, per- it—and nominate. haps at a recent conference, who gave an excellent seminar —Lori Bibb 3 The NIH Catalyst Research Festival Regenerative Medicine continuedfrom page 1 de-differentiation; “sternness” genes, on ceramic particles) supports both bone for- dynamic mechanical stimulation (cyclic the other hand, were found to support MSC mation and the stem cell, so that marrow tensile loading) enhanced tenogenesis, self-renewal and proliferation—“differen- can be formed. The size and shape of the Kuo developed engineering devices and tiation readiness”—in the undifferentiated scaffold, which organizes and controls the tools to place the constructs under either state. structure of the bone formation, also mat- static or dynamic tension. A proper scaffold to support these stem ter, she added. She observed a similar increase in col- cells, Tuan determined, would mimic the Among research questions requiring lagen mRNA in both static and dynamic native extracellular matrix and be able to attention, Robey said, are determining the conditions, but noticed more matrix depo- fit into a three-dimensional groove. number of cells necessary for successful sition and persistent scleraxis expression Nanofibers of collagen and other macro- transplantation, identifying an appropri- over time with cyclic loading. In addition, molecules are the hallmark of the extra- ate transplantation method, stimulating in- expression of matrix metalloproteinases cellular matrix of skeletal tissues, Tuan corporation of the transplant into the pre- such as collagenase and gelatinase were said, explaining how his group used existing tissue, and developing a root differentially regulated by cyclic loading, electrospinning to prepare similar structure in order to reconstruct a viable implying that the increased matrix depo- nanoscale fibers from a biodegradable tooth from dental pulp cells. sition and resulting tenogenic differentia- polyester and then produced the desired tion are regulated by changes in the ex- tissue-engineering scaffold. Kuo: Mechanoactive Tenogenesis pression of these genes. Their next step was to optimize nutri- Catherine K. Kuo, a postdoctoral fellow ent supply to the developing cartilage con- in the NIAMS Cartilage Biology and Or- Dunbar: Thwarting Mutagenesis struct to grow in size; the team succeeded thopaedics Branch, brings her engineer- PI Cynthia Dunbar and her colleagues in enhancing growth of the engineered ing perspective to investigating the po- in the Hematology Branch, NHLBI, have cartilage in vitro from a diameter of 1.5 tential of MSCs in tissue engineering and been using gene-transfer techniques in cm a few years ago to around 4 cm today. regenerative medicine. Kuo is particularly their research on hematopoiesis. Finally, the researchers are using mini- interested in the regeneration of tendons, Addressing the safety issues and com- pig and rat models to test the ability of the which transmit forces from the muscle to plications associated with the use of viral engineered cartilage construct to repair the bone, and ligaments, which join bone transfer vectors, the group has investigated cartilage defects and integrate into native to bone and thus stabilize joint structures. the risks of insertional mutagenesis after cartilage. Initial observations have revealed Nearly half of all skeletal injuries involve retrovirus and lentivims gene transfer to promising signs of tissue repair in six tendons and ligaments. Poor healing abil- hematopoietic stem cells (HSCs). months and four weeks in these respec- ity of these tissues and imperfect repair Viral gene-transfer vectors that are used tive models, Tuan said. strategies provide an opportunity for re- to target HSCs must integrate into the host generative therapies. genome to be effective, but depending on Robey: Skeletal Cells and Scaffolds There are no known growth factors to the site of insertion, they can activate ad- When bone-marrow skeletal stem cells induce differentiation of MSCs into ten- jacent genes, including protooncogenes. are plated, they are able to form cartilage don/ligament fibroblasts (tenogenesis). These issues did not emerge in studies in- in vitro, and when they are transplanted, These cells are distinct from other mus- volving murine models and have come to they form bone, marrow, fat, and the culoskeletal lineages in that mechanical light during clinical gene-therapy studies, stroma that supports blood formation. This stimulation is the only known factor able Dunbar said. multipotentiality suggests broad therapeu- to induce tenogenic differentiation of In one study, patients with X-linked se- tic application for dental and craniofacial MSCs. Kuo created tendonlike constructs vere combined immunodeficiency (SCID) reconstruction, observed Pamela Robey, by seeding three-dimensional collagen had reconstitution of their T-cell immu- chief of the Craniofacial and Skeletal Dis- type I gel scaffolds with MSCs; she cul- nity and clinical improvement after HSC eases Branch, NIDCR. tured the constructs under uniaxial static gene therapy. This optimistic outcome was Robey and her team have been charac- or dynamic tension. interrupted three years later by the devel- terizing these stem cells and evaluating Kuo monitored tenogenesis via expres- opment of T-cell leukemias in four pa- different scaffold choices for tissue regen- sion of scleraxis, a transcription factor that tients, due to activation of a growth-pro- eration. The identification of markers for uniquely marks tendon progenitors dur- moting gene by the inserted gene-therapy skeletal stem cells will aid the quality of ing development. To determine whether continued on page 5 purification of these cells from bone mar- row. It will, however, also be necessary Engineering and Physical Sciences SIG Starting Up to generate large numbers of these cells via ex vivo expansion. The goal, explained he Working Group on Women in Bio- biomaterials, nanotechnology, physical Robey, is to trick the stem cells into divid- T medical Careers subcommittee on In- regulation in biology, engineering-based en- ing symmetrically to keep them as tegration of Women into Bioengineering abling technologies, and quantitative ap- multipotent as possible. Fields has created the Engineering and proaches based on physical sciences. engi- In addition to researching ways to iso- Physical Sciences Special Interest Group. This SIG will organize seminars by this will to promote neers and physical scientists from inside and late and expand the skeletal stem cells, The goals of SIG be outside identify available Robey’s group has been testing potential interaction between investigators and labo- NIH and mentors ratories whose research interests involve to engineering and physical science stu- scaffold materials. Currently, there are only integrating engineering or physical science dents and fellows at NIH. Particular efforts a few FDA-approved, commercially avail- with biology, and to educate the NIH com- will be made to identify outstanding women able scaffolds. The nature of the scaffold munity about these approaches. engineers and physical scientists. Contact is important, said Robey, observing that Areas of research interests include tissue Catherine Kuo ( 4 November — December 2007 Getting to the Bottom of the Beta Cell continuedfrom page 1 conversely, a knocked-in point mutation yields “huge islets and increased beta cell mass.” The knock-in cohort demonstrates in- creased regeneration potential via differ- entiation of stem cell-like progenitors in the pancreatic duct, increased beta cell proliferation, and accompanying function- ality reflected in superior glucose toler- ance, insulin secretion in response to glu- cose, and protection against streptozoto- cin-induced diabetes. The team intends to explore the regen- erative potential of other cell-cycle pro- Fran Pollner teins as well, Rane said. Beta Cell Mates: to right) chair (left symposium Sushil Rane, NIDDK, Jurgen Wess, NIDDK; Marvin Gershengorn, NIDDK; Josephine Egan, N1A; and David Rough Measures Harlan, NIDDK Accurate measurement of pancreatic beta cell mass, a key indicator of beta cell Pathways to Treatment hanced insulin release and improved function that could elucidate diabetes pro- Introducing her research into islet biol- glucose tolerance, suggesting that “thera- gression and assess response to treatment, ogy to discern new approaches to treat pies aimed at enhancing this pathway is in a “sony state,” said Dave Harlan, chief type 2 diabetes, Josephine Egan observed might be useful in the treatment of type of the Diabetes Branch, NIDDK. He apolo- that the workings of the pancreatic islet 2 diabetes,” said Wess, chief of the Mo- gized for a talk that would highlight ques- cells are only inferred from changes in lecular Signaling Section, Laboratory of tions eluding answers and somewhat dis- hormone levels in response to stimulants. Bioorganic Chemistry, NIDDK. appointing research results. The disordered responses that trumpet The team has also created a series of PET imaging using dihydrotetraben- diabetes onset provide clues to treatment mutant M 3 muscarinic receptors that are zene (DTBZ), the radioactive ligand for strategies, said Egan, senior investigator unable to bind acetylcholine (the endog- the vesicular monoamine transporter-2 and chief of the Diabetes Section of the enous neurotransmitter) but can activate found in pancreatic beta cells, has been Laboratory of Clinical Investigation, NIA. different classes of G proteins when getting a lot of attention as a potential These derangements include decreased treated with the pharmacologically inert noninvasive method to measure beta cell insulin secretion; the loss of the pulsatility compound clozapine-N-oxide (CNO). mass, Harlan said. of insulin release, a reflection of beta cell Wess discussed findings in transgenic He noted that PET images obtained dysfunction; blunted response of the gut mice that selectively express these re- from pancreas-transplant recipients reveal protein glucose-dependent insulinotropic ceptors in their pancreatic beta cells. a bright signal from the transplanted or- polypeptide (GIP); increased glucagon se- CNO treatment of different transgenic gan, while the individual’s native pancreas cretion; and increased pancreatic polypep- mouse lines resulted in the selective ac- sends out a signal; so, results tide - low even secretion. tivation of either Gq or G s -type G pro- from individuals with long-standing type Among agents Egan has been explor- teins in pancreatic beta cells. In both cass, 1 diabetes have been inconsistent—as ing is GLP-1, another gut hormone, which, acute CNO administration led to a sig- have results in monkey studies. For in- unlike GIP, releases insulin and normal- nificant increase in insuin release and stance, autopsy findings show that the izes blood sugar in patients with diabetes improved glucose tolerance. ligand binding is not specific in monkey and appears to correct imbalances more Key questions that remain to be ad- pancreatic beta cells. effectively than exogenous insulin. dressed, Wess, said, are: What are the “We conclude that DTBZ PET scan sig- Jurgen Wess and his colleagues have chronic effects of activating these differ- nals do not accurately measure pancre- generated a series of mutant mouse mod- ent signaling pathways—or a mixture of atic beta mass,” Harlan said, adding that els to better understand the role of M, mus- both—on insulin synthesis and release though beta cell regeneration may occur carinic acetylcholine receptors in beta cell and beta cell mass and survival, and how in vivo—at least in mice—improved func- function. The selective overexpression of can these findings guide the develop- tion has not yet been shown in humans. M 3 receptors in beta cells leads to en- ment of novel therapeutic agents? 11 Regenerative Medicine rus [SIV] ) integration sites. The integration taining integration events in the Mds 1/Evil continuedfrom page 4 sites were determined in circulating granu- gene complex, suggesting significant in vector. locytes and lymphocytes of the monkeys vivo selection for these clones, a veiy wor- The need for an experimental model up to seven years post-transplantation. risome pattern, Dunbar noted. One more predictive and more closely related The researchers observed that integra- macaque developed leukemia due to in- to humans prompted Dunbar’s laboratory tion was nonrandom: MLV integrated sertional activation of the BclaAl locus. to turn to the rhesus macaque as a model around transcriptional start sites; SIV inte- Dunbar discussed approaches to de- organism for studies of gene therapy. gration sites were evenly spaced along the crease the risk of insertional mutagenesis, Dunbar’s group took advantage of the length of a gene. including alternative vector systems and rhesus macaque model to study the pat- The researchers also noted that animals modification of current vectors to decrease terns of virus (either murine leukemia vi- receiving MLV-transduced HSCs had the likelihood of activation of adjacent rus [MLV] or simian immunodeficiency vi- marked overrepresentation of cells con- genes. H 5 The NIH Catalyst Chemistry: From the Beaker to the Bedside by Fran Pollner hey stopped short of saying “Chem- istry rocks!” but the Research Fes- T tival panelists presenting their work “From the Beaker to the Bedside” did not blunt their reverence for chemistry in the quest for diagnostic probes, thera- peutic agents, and innovative paths to elucidating the nature of pathogenic pro- cesses. Designer Drugs Nigel Greig and Amy Ffauck Newman elaborated on some of their efforts to synthesize drugs aimed at treating Alzheimer’s disease and addiction, re- spectively. Their ultimate objective is tech transfer. Newman’s laboratory has synthesized dopamine D, receptor ligands and dem- onstrated their selective localization and binding in the nucleus accumbens in rat Fran Pollner brains, as well as their ability to thwart Chemists . (left to right) Nigel Greig, NIA; Daniel Appella, NIDDK; Amy Hauck Newman, the compulsion to cocaine relapse in NIDA; Craig Thomas, NIH Chemical Genomics Center; and panel chair Matthew Hall, NCI squirrel monkeys. The D 3 receptor antagonists are not a the nausea and vomiting that may accom- Thomas listed several other projects “golden bullet” against all aspects of ad- pany phenserine, the drug is better toler- undertaken with both intramural and ex- diction, observed Newman, senior inves- ated in humans and can be administered tramural labs that involved in silico dock- tigator and chief of the Medicinal Chem- in higher doses (120 mg compared with ing, virtual screening, advancing cellu- istry Section, Medications Discovery Re- 15 mg), he said. He speculated on the lar pathway assays, and uncovering un- search Branch, NIDA. “They will not possible value of combining the two. foreseen toxicity in a potential therapeu- block self-administration of cocaine [in tic agent. squirrel monkeys], but they are very ef- Molecules and Probes A major focus of Appella’s group in fective in the relapse model.” Providing the molecular tools to iden- the Laboratory of Bioorganic Chemistry, The team currently has a “lead candi- tify, interrupt, or otherwise manipulate NIDDK, is manipulating peptide nucleic date” among the compounds under study pathogenic and genetic mishaps is the acids (PNAs) to improve their ability to and is pursuing ways to optimize its daily work of Craig Thomas and Daniel bind to DNA. What’Chemically modify- bioavailability and functionality. Appella, whose efforts serve the needs ing these backbone units to improve their Greig, chief of the Drug Design and of investigators across the NIH institutes. DNA binding affinity and sequence Development Section and senior inves- One such need was reflected in the specificity in a predictable manner is tigator, Laboratory of Neurosciences, NIA, question, “Could a misfolded protein re- aimed “not so much at making a drug traced the development of synthetic ana- fold with the aid of a chemical chaper- but at developing a tool—for instance, logues of physostigmine—from the Phy- one?” Thomas recalled. to identify a pathogen” and improve di- sostigma venenosum plant—through The answer was critical to devising a agnostic assays, Appella said. their testing first in animals and then in new approach to Gaucher disease, a ly- A project to stabilize PNA-DNA du- clinical trials in patients with Alzheimer’s sosomal storage disorder characterized by plexes—and, more recently, quadru- disease. 200 point mutations in the glucocereb- plexes—by incorporating cyclopentane The novel agents—phenserine, a se- rosidase (GC) gene. NHGRI’s Ellen into different PNA sequences “has been lective acetylcholinesterase inhibitor, and Sidransky brought the question to the a synthetic challenge—now in its third its enantiomer, posiphen—were designed NIH Chemical Genomics Center (NCGC). iteration,” Appella recounted, “but we to inhibit the synthesis of the amyloid-p Quantitative high-throughput screening have demonstrated, after a lot of work, precursor protein (APP). facilitated the identification of three novel that binding Is improved.” Both have been found to lower APP structures with potent selective inhibition The group has synthesized PNA cap- and amyloid-P in mouse brains, and both of GC, said Thomas, chemistry group ture and detection probes and is work- have moved into clinical trials. Results leader at the NCGC. ing on sidechain incorporation to de- thus far with phenserine are promising, “But optimizing was a challenge” that velop improved light-up probes. The Greig said, showing a dose-related low- took four months and five rounds of syn- team developed a “PNA sandwich-hy- ering of amyloid-p plaques compared thesizing nearly 300 compounds before bridization” assay that can be used to with placebo. the team delivered four novel chemotypes distinguish protective antigen from an- Posiphen, now in phase 1 clinical trial, across the potency range of GC inhibi- thrax. The lab’s latest project involves may prove more beneficial than tion with the potential of binding to the tethering three PNA sequences together phenserine, he added. Cholinergically enzyme to restore shape and function, that simultaneously clamp onto DNA to inert and therefore not associated with he related. form a highly stable complex. 6 November — December 2007 Research Festival Forestalling Blindness: Two Decades of Progress by Fran Pollner hree spotlights have converged on the eye over the past 20 years, il- T luminating the genetic underpin- nings of eye disease, the immunological environment of the eye, and the environ- mental modifiers of inborn propensities to eye disorders. Following these pathways leads to for- midable strategies to combat retinal neurodegeneration and choroidal neo- vascularization, the major instruments of blindness, panelists agreed at a Research Festival symposium focused on recent advances in eye research. The panelists, all NEI investigators, were themselves in- Fran Pollner struments of many of these advances. it: Michael The eyes have (NEI colleagues, left to right) Paul Sieving , symposium co-chair Redmond, Emily Chew, co-chair Patricia Becerra, Juan Amaral, and Robert Nussenblatt RPE65 In the early 1990s, the lab of Michael (CNTF )—was encapsulated within a semi- Robert Nussenblatt, head of the Labora- Redmond identified and cloned the RPE65 permeable intravitreal implant. The im- tory of Immunology. gene. Since that time, researchers have plant was removed after six months, but The therapeutic implications of this per- found more than 60 mutations in its 14 retinal cells continued to secrete CNTF, spective are now being investigated in an exons, all causing eye disease ranging from possibly as a result of persisting vitreous NEI clinical trial of the anti-inflammatory early-onset severe disease to milder late- nourishment, Sieving remarked. agents inflixamab, sirolimus, and dacluzi- onset phenotypes. Half were missense mu- The CNTF-implanted eye showed a mab to treat choroidal subretinal neovascu- tations. The team looked for mutations in trend to higher acuity, with several of the larization in patients with AMD, said patients with Leber congenital amaurosis patients demonstrating a three- to four- Nussenblatt, the trial PI. He noted that res- (LCA) and childhood-onset severe retinal line improvement in reading the eye chart toration of the downregulatory immune dystrophy—two of the earliest blinding in the treated eye. “The patients’ enthusi- environment of the eye is the hoped-for conditions—and found them, recalled asm was gratifying; they wanted implants therapeutic mechanism. Redmond, chief of the Molecular Mecha- in their other eye as well,” Sieving said. “But while this is a great idea,” he added, nisms Section in the Laboratory of Retinal “we don’t know that these medications will Cell and Molecular Biology (LRCMB). PEDF achieve that goal. Rather, we are treating The lab developed an expression sys- Pigment epithelium-derived factor the result of the immune dysregulation.” tem and proved that RPE65 is required (PEDF) is another agent that has passed for the production of 11-cis retinal, essen- Phase I human safety tests. “It is neu- AREDS and AREDS2 tial for vision. They generated Rpe65- rotrophic, antitumorigenic, antiangio- Whatever the genetic and immune com- knockout mice that could not produce li- genic, and anti-inflammatory—it is a veiy ponents of AMD, the ability of a regimen ds retinal and lacked rhodopsin. versatile protein,” said Juan Amaral, a staff of antioxidants, copper, and zinc to stem The lab has also been involved in gene scientist in Patricia Becema’s Section of Pro- progression in patients with moderate therapy studies involving dog LCA mod- tein Structure and Function, LRCMB. PEDF AMD speaks loudly to the role of nutri- els, in which functional recovery of the was also cloned in the early 1990s in the tion in warding off an otherwise relentless treated eye has been demonstrated on LRCMB and has been studied extensively disease course, observed Emily Chew, electroretinogram. Four early-phase clini- in this lab deputy director of the Division of Epide- cal trials are currently underway in the Using rat models, Amaral and Becerra miology and Clinical Research and chief United States and abroad, Redmond noted. have been exploring the potential for of the Clinical Trials Branch. therapeutic delivery of this protein. “We The trial regimen in the NEI-sponsored CNTF propose subconjunctival delivery, either Age-Related Eye Disease Study (AREDS), As of a year ago, said NEI Director Paul by injection or, simpler and safer, a sus- which involved nearly 5,000 patients, Sieving, 117 genes contributing to the tained delivery device,” he said, noting that yielded a 25 percent reduction in progres- death of photoreceptor cells had been the team has documented rapid diffusion sion to advanced AMD. The regimen has cloned. Animal work with neurotrophic to relevant areas, with intense scleral, cho- become a standard nutritional supplement protective factors has shown that such lost roidal, and retinal signals. for patients with AMD and, if taken by all vision is salvageable. Subconjunctival injections of PEDF pro- at-risk individuals, could be expected to A neurotrophic protective factor with teins can inhibit progression and induce prevent progression in about 300,000. demonstrated photoreceptor-rescue abil- regression of laser-induced neovessels in AREDS2 is currently recruiting 4,000 ity in 13 different rat and mouse mutants the choroid of rats, Amaral said. people into a five-year study of the effects with retinal degeneration was put to the on AMD of co-3 long-chain polyunsaturated test in 10 retinitis pigmentosa patients in Immune Mediation fatty acids and the antioxidant carotenoids a Phase I NEI study. Not only was safety The mechanisms underlying atheroscle- lutein and zeaxanthin. Chew noted that shown, but potential efficacy was prom- rosis also underlie choroidal neovascular- lutein is now viewed as a substitute for (3- ising enough to warrant a move to Phase ization and age-related macular degenera- carotene, shown in two NCI-supported II, said Sieving, the study PI. tion (AMD)—they are all inflammatory, im- lung cancer trials to increase lung cancer The agent—ciliary neurotrophic factor mune-mediated conditions, suggested and mortality risk among smokers. M 7 — . / The NIH Catalyst Research Festival Chromosomes in Modern Biology and Medicine: A Looking Glass into Common Diseases byJulie Wallace Francis Collins The Genetics of Common Disease Efforts to uncover the genetics of com- mon disease are “rocketing forward” thanks to a revolution in genomic tools and technologies and the emergence of new, multidisciplinary collaborations, said NHGRI Director Francis Collins. A huge leap forward was the recent creation of a map of common human genetic variation, called the HapMap. The HapMap confirmed that variations in DNA sequence—single nucleotide polymorphisms (SNPs)—travel in neigh- borhoods, called haplotypes. More im- portant, the map paved the way for ge- nome-wide association studies (GWAS), Julie Wallace a new approach that involves rapidly Understanding chromosomes: (left to right) Shiv Grewal, NCI; Thomas Ried, NCI; session scanning SNPs across the genomes of chair John Niederhuber, NCI director; Gary Felsenfeld, NIDDK: and Francis Collins, NHGRI many affected and nonaffected people to find genetic variations associated with mosomal abnormalities in blood cancers is a continuous selection for and mainte- a particular disease. has been definitively recognized with the nance of aneuplodies that are not fatal to An impressive array of NIH-led initia- identification of the Philadelphia chromo- cells, but rather confer “stability on a dif- tives, including the Genetic Association some in chronic myeloid leukemia and ferent plateau.” Information Network and the Genes, En- other translocations in lymphomas, Tho- These aneuplodies are tumor-specific vironment and Health Initiative, have mas Ried observed. He then addressed and acquired early in tumorigenesis, sug- the complexities in diagnosis. been launched to tap into this powerful of chromosomes and gesting they may be useful resource. Data generated by these and solid tumors. Ried’s laboratory is currently investigating Chromosomes in epithelial cancers are mouse models of hematological malignan- other NIH-supported GWAS are already defined by catastrophic mitoses and cen- cies such as Burkitt’s lymphoma and of being deposited in the Database of trosome amplifications that lead to cells mammary gland adenocarcinomas. Genotype & Phenotype (dbGAP), a with abnormal chromosome numbers, In addition to studying mouse models, powerful database developed by NCBI complex karyotypes, and ongoing chro- Ried is particularly interested in looking for use by the scientific community, mosome instability, noted Ried, head of at the entire transcriptional landscape of Collins said. To access dbGAP, go to the Cancer Genomics Section, Genetics cells with aneuploidies, addressing what Research Festival lar Biology, NIDDK. As a result of thor- ence or absence of various modified his- regulatory sites and is displaced through oughly characterizing the chicken (3-globin tones throughout the chicken (3-globin lo- nucleosome-disrupting activities such as locus, Felsenfeld’s lab identified a specific cus, Felsenfeld’s laboratory discovered that transcription. DNA sequence that is capable of blocking nucleosomes at the insulator are highly By studying the salt-dissociation prop- enhancer-promoter interactions. DNA in- marked with modifications frequently as- erties of nucleosomes containing differ- sulators, as these sequences are termed, sociated with open chromatin. ent combinations of these variants, are found in different places in the ge- Further studies established that a Felsenfeld’s group has been able to de- nome and help form boundaries by block- heterodimer—USF1 and USF2—binds the termine a hierarchy of nucleosome sta- ing inappropriate interactions within the insulator and recruits the histone H4R3- bility. Nucleosomes with both H3.3 and nucleus. specific methyltransferase PRMT1 and, sub- H2A.Z are highly unstable, Felsenfeld said. Felsenfeld’s group identified a single sequently, a barrage of “positive” histone These nucleosomes are predominantly protein in vertebrates, CTCF, for its ability modifications to maintain a local environ- found on the promoters of transcription- to bind the chicken (3-globin insulator and ment of open chromatin. ally active genes and over the coding re- confer insulation. Recent studies of CTCF Nucleosome stability can also play a role gions of genes transcribed at high levels, have begun to elucidate its genome-wide in regulation of chromatin-coupled mecha- suggesting that these histone variants can locations as well as the role of CTCF sites nisms, Felsenfeld’s group has recently dis- serve as an epigenetic signal in the ge- in mice that mediate the formation of DNA covered. In addition to regulation of his- nome. loops and higher-order structures. tones by modification, histone variants In addition to their enhancer-blocking such as H3.3 and H2A.Z are incorporated Shiv Grewal—Heterochromatin: role, DNA insulators can act as barriers to into nucleosomes and can mark specific A Versatile Platform of the Genome block the spread of condensed chroma- sites in the genome. Continuing Felsenfeld’s theme of con- tin. By systematically analyzing the pres- In particular, H3.3 is concentrated at text within chromosomes, Shiv Grewal continued on page 10 Genome-wide SNP Assays and the Genetics of Normal and Abnormal Variation byJulie Wallace disease course. In a study of 96 children diagnosed with tephen Chanock, head of the schizophrenia by age 12, Genomic Variation Section, Addington’s group identified S Pediatric Oncology Branch, multiple chromosomal aber- NCI, is using genome-wide SNP rations, including a novel bal- assays to study solid tumors. anced translocation between He and his colleagues are aim- chromosomes 1 and 7, three ing to identify genetic regions as- cases of X chromosome ab- sociated with risk for specific can- normalities, and four cases of cers, such as breast and prostate a 3-Mb deletion on chromo- cancer. The results of their initial some 22qll, associated with screening of more than 540,000 velocardiofacial syndrome. SNPs prompted further exploration Copy number variants— Julie Wallace of a specific chromosomal region DNA segments larger than 1 Traveling the genome: (left to right): Stephen Chanock, NCI: (8q24) commonly amplified in kb that are present in abnor- Francis McMahon, NIMH: session chair Andrew Singleton, NIA: mal numbers—were also prostate tumors. Moreover, regions and Anjene Addington, NIMH in a 1.5-Mb section of this locus higher in children with COS were also implicated in breast and colon nent. Using samples from the NIMH Ge- than their unaffected siblings (an aver- cancers—leading to the tantalizing sug- netics Initiative Bipolar Disorder Consor- age of 32 compared to 24). These varia- gestion, Chanock said, that this may be tium, McMahon’s lab identified around 80 tions suggest “general genomic instabil- one of several master-regulator regions SNPs in or near genes. ity,” Addington said, but noted that it is important in different cancers. In this “first look” at bipolar disorder, a not easy to distinguish disease-related Chanock’s group is now extending its significant SNP was found near the DGKH from garden-variety copy number varia- focus to pancreatic, lung, and bladder gene, a good candidate gene for mental tions. cancers. illness that is related to lithium signaling. The study also suggested the involvement Homozygosity and Complex Diseases Bipolar Disorder of several risk alleles in bipolar disorder, While genotyping large numbers of which may be the “result of many genes Caucasian males, Andrew Singleton, an In the realm of psychiatric diseases, of small effect acting together,” McMahon investigator in the Molecular Genetics where patients are primarily diagnosed said. Unit, Laboratory of Neurogenetics, NIA, by behavior, “reliability in the diagnosis and his colleagues observed large tracts does not equal validity [in molecular ge- Childhood-Onset Schizophrenia of allele homozygosity in 7 percent— netics],” and the underlying biology for Anjene Addington, also of NIMH, is finding that suggested a single origin for each patient not necessarily relate may charting the chromosomal aberrations and maternal and paternal chromosomes. Of to their psychiatric label, observed Francis copy number variations in patients with these 7 percent, 59 percent possessed at McMahon, chief of the Genetic Basis childhood-onset schizophrenia (COS). She least one homozygous region greater Unit, Mood and Anxiety Disorders Pro- hopes to identify a homogenous group of than 5 Mb in size. Identifying homozy- gram, NIMH. patients less likely to have been exposed gous populations, Singleton said, should To limit this variable, McMahon’s lab to environmental factors. Patients with enhance the power of genome-wide as- focuses on bipolar disorder, which ap- early-onset disease are also thought to have sociation studies of complex traits and pears to have a strong genetic compo- a greater genetic risk and a more severe diseases such as Parkinson’s. 9 — Research Festival Uncovering Secrets in Sweat: Stress and Immune-related Biomarkers by Evan Galloway t the NIH Research sion, even though they were Festival symposium medicated and in remission A on a new noninvas- at the time of the study. ive method for detecting Psychophysiologist Julian stress and immune-related Thayer, of Ohio State Univer- biomarkers in sweat, immu- sity in Columbus (and for- nochemist Terry Phillips de- merly of NIA), is now veri- scribed his work as “pulling fying these results against an- nothing out of nothing.” other measure of stress However, the “nothing” he heart-rate variability. A de- wrings from a tiny sponge crease in heart-rate variabil- soaked in sweat can reveal ity, especially while sleeping, the emotional state of the indicates an increased likeli- sweat’s producer. hood of heart disease. How- The motivation for this ever, it may also signify an project, neuroendocrinolo- in stress. Evan Galloway increase gist Esther Sternberg re- In a previous study, when Sweat equity?: (left to right) Julian Thayer, Ohio State University; Esther counted, was the request Thayer and his colleagues Sternberg, NIMH; Andrea Marques, NIMH; and Terry Phillips, NIBIB from some architects for a told healthy study subjects noninvasive way to measure the stress lev- that was gathering dust in his lab. After that they would have a test in the morn- els of employees in traditional and mod- developing a protocol for cleaning the ing, they displayed decreased heart rate ern workplace environments. sweat sample of salt and recovering the variability at night compared with other The architects wanted to design better integral proteins, he then created a healthy subjects who were simply told to offices. Sternberg, director of the Integra- microfluidic chamber for high-sensitivity return to the lab in the morning. Interest- tive Neural Immune Program and chief of recycling immunoaffinity chromatography. ingly—especially to the architects—when the Section on Neuroendocrine Immunol- The next step was to test this assay in a applying this method to office workers, ogy and Behavior, NIMH, envisioned a clinical setting, continued Andrea Marques, the researchers found that working in a case study of the interdisciplinary devel- a postdoc in Sternberg’s section. A com- more modern workspace was associated opment of an assay. parison of the levels of neuroimmune with an increase in heart-rate variability. The first step was to develop a collec- biomarkers in the sweat and plasma of Although Thayer’s group has not fin- tion method. A small absorbent skin patch depressed women and healthy volunteers ished comparing the results of the two ap- was already commercially available. The enrolled in an ongoing study of osteoporo- proaches in the office workers, they an- trick was in squeezing it dry. sis in women with depression led by ticipate that the use of both sweat-patch Phillips, chief of the Nanoscale Immu- Giovanni Cizza, NIDDK, revealed an abun- biomarkers and heart-rate variability will nodiagnostic Group at NIBIB, tried differ- dance of proinflammatory cytokines and be helpful in establishing the status of the ent centrifuge-and-squeeze approaches stress-related neuropeptides in both the subjects’ stress responses from two differ- before settling on a solid-phase extractor sweat and plasma of women with depres- ent perspectives. H Chromosomes and Common Diseases continuedfrom page 9 focused on the organization within chromosomes of so-called fication, transcriptional silencing, RNAi, chromosomal archi- “junk” DNA—which, he observed, not only constitutes a sig- tecture, and chromatid cohesion. Specifically at the mating- nificant fraction of eukaryotic genomes, but also contributes to type region, heterochromatin is necessary for the spreading regulating cellular processes and genomic evolution and sta- of the RNA-inducecl initiation of transcriptional gene-silenc- bility. ing complex and also inhibits RNA polymerase II from local- Senior investigator and head of the Chromosome Biology ization to these sites. Section, Laboratory of Biochemistry and Molecular Biology, Grewal’s group recently identified a multiprotein effector NCI, Grewal has paid special attention to heterochromatin. complex, called SHREC, that coats all major heterochromatin Within the fission yeast Schizosaccharomyces pombe, there domains and contains the histone deacetylases CLR3- This are distinct peaks of heterochromatin, marked by the presence complex is recruited to heterochromatin in both RNAi-de- of a specific histone H3 modification on lysine 9 (H3K9), which pendent and -independent manners. recruits heterochromatin protein 1. These peaks are found at Grewal’s work has contributed to challenging the dogma centromeres, telomeres, regions of ribosomal DNA, and the that heterochromatin is a static, rigid structure. Rather, Grewal mating-type locus. and his team are discovering heterochromatin changes Grewal’s studies of these regions has revealed a role for throughout the cell cycle. Their ongoing studies on the dy- small RNAs in the formation of heterochromatin: In a self-rein- namic regulation of heterochromatin have provided new in- forcing loop mechanism, repeats in the DNA sequence in these sights into the mechanisms of heterochromatin assembly, regions are transcribed and resulting RNAs are processed into Grewal said. small RNAs that lead to the recruitment of H3K9 methyltrans- The establishment and maintenance of these important het- ferases and the spreading of heterochromatic marks. erochromatic sites, he said, are conducted through a care- More recent work has demonstrated that heterochromatin fully orchestrated dance of histone modifications and protein can recruit diverse regulatory proteins involved in histone modi- binding. 10 November — December 2007 Research Festival Job Fair: Exploring the World of Work Beyond the Research Festival text and photos byJulie Wallace ore than 40 exhibitors—among and spoke to no fewer than seven dif- order to know exactly what to ask rep- them industry giants, local ferent companies fitting those descrip- resentatives about specific job oppor- M biotech companies, govern- tions. tunities. ment agencies, professional societies, NCI postdoc Christine Horak arrived Thomas Paul, an NCI fellow and Job and foundations—were staffing tables early, which gave her easier access to Fair committee co-chair with Catherine and collecting resumes the third day at the much-visited Genentech table. Seek- Kuo of NLAMS, declared the Job Fair a the Job Fair, the centerpiece of the third ing a position involving oncological drug success, with a “record number of ex- day of the NIH Research Festival. discovery and development in the phar- hibitors, who were “thrilled with the Based on the comments of randomly maceutical industry, Horak said the quality and quantity of applicants.” selected fellows traversing those tables, Genentech representatives were “ex- Sponsored by OITE and the Office one would conclude that preparation tremely helpful, [taking] time with my of Research on Women’s Health, the for the Job Fair had been on target and CV and [telling] me exactly what their Job Fair is an annual event held in con- the array of potential employers and requirements are for hiring scientists.” junction with the NIH Research Festi- positions encouraging. NCI postdoc Jennifer Seiler checked val. It provides a “unique opportunity NIDDK postdoc Peter Choi was es- out possible project-management posi- for NIH fellows to meet face-to-face pecially interested in a biotech and/or tions and found several appealing pro- with potential employers,” Paul ob- defense contractor research position spective employers, including Discov- served. ery Logic Rockville, Md.), Lockheed “In today’s environment, where most Martin (headquartered in Bethesda, job applications are done online, the Md.), and the FDA. personal interaction and one-on-one In general, the fellows interviewed by networking fellows encounter at the the Catalyst said they were well-pre- Job Fair can make them stand out pared for the Job Fair. They cited two amongst a sea of applications that a seminars earlier that month sponsored company receives. . . . [not] just a re- by the Office of Intramural Training and sume, but a person behind a body of Education (OITE) specifically designed work and experience,” Paul said. 0 to help fellows craft their C.V.s and resumes and to navigate the Job Fair in the most useful ways. Choi, Horak, and others also remarked on the advisability of checking the online postings that are generally made avail- Sandeep Dayal , considers , NIDDK applying for an AAAS Science & able a few weeks before the Job Fair in Technology Policy Fellowship. their Fellows await turn at the Jennifer Seiler, NCI, discusses job Genentech (headquartered in opportunities with a rep from South Scm Francisco) table Activity around the FDA table BioReliance (North American headquarters, Rockville, Md.) Ejaz Shamim, NINDS, hands out Melinda McFarland, NIMH, Peter Choi, NIDDK, inquires about information about the Fellows with a representative programs at The Biotechnology speaks Committee Institute, Arlington, Va. from SAIC, Frederick, Md. 11 . The Embedded Librarian: NIH Informationists by Cindy Clark Click into Chemistry and Tech Transfer he information needs of NIH researchers tend to be informationist, she said, “might best be characterized as knowl- highly specialized. Consider the working world of edge management—database development, such as linking T chemists and the technology-transfer specialists who ac- structures to relevant citations; data and document curation; tively promote discoveries made at NIH. Like many special- and even text and data mining.” ists, they have a specific language that condenses communi- An informationist might well introduce the research team cation. to new software tools—such as the electronic lab book—and When NIH chemists, investigators, or analysts need to find other new information resources, she said. information, informationists who understand their language An informationist might also search databases that require can be an enormous help. special expertise, such as patent databases. Their specializa- Now in its sixth year of collaborating with NIH researchers, tion enables informationists not only to “find the answers but the NIH Library’s Informationist Service employs 14 informa- also to anticipate the questions,” Grefsheim observed. tion specialists who work with research groups across the As for the future, Grefsheim anticipates a growing demand spectrum of NIH institutes, divisions, and programs.* from both clinical and basic researchers for the services of “In the past,” NIH Library Director Suzanne Grefsheim said, bio-informationists, especially to organize and analyze the mas- “[our] informationist services focused primarily on clinical sive amounts of genetic information flowing from the Human researchers, but we always thought basic scientists such as Genome Project and similar initiatives. chemists would find the service beneficial. Before reaching out to this community, however, it was a matter of hiring li- * For background information on the NIH Library Informationist brarians with the subject expertise needed to provide the rel- Service, see “The ‘Embedded Librarian’: NIH Infomiationists Become evant customized service.” Team Players,” Doe NIH Catalyst, Nov.-Dee. 2005, available online at What scientists such as chemists might appreciate from an Good Chemistry arbara Brandys joined the NIH Li- (LCC), has worked with Brandys B brary in 1997 and became an for more than five years. “One of informationist in 2004. She provides the challenges we were struggling information services to various NIH with was setting up a website for groups, including the Drug Informa- compounds. We needed the stme- tion Service at the Clinical Center. tures and data uploaded,” said After receiving her undergraduate Keefer. degree in chemistry, she worked as a Brandys joined on to convert science teacher and then as a chemist the structures to images and en- in the private sector. Brandys speaks hance links to relevant data and several languages, including English, publications for the Nitric Oxide Hebrew, and Polish, and also serves Donors database. as a volunteer translator in the Clini- The LCC patents compositions cal Center. of matter with the intention of Larry Keefer, head of the Chemis- making them widely available for Michael Walden Informationist Barbara Brandys displays try Section and chief of the NCI Labo- pharmacological screening. If a chemistry structure data she enhancedfor Larry ratory of Comparative Carcinogenesis compound has a commercial ap- group the Laboratory Comparative plication, Keefer’s at of Carcinogenesis, NCI say, as an ef- fective anticancer obtained through pound in it, she pulls chemical param- NIH. eters from the methods section and up- Brandys’ knowl- loads them to the database.” edge of chemistry Brandys specializes in chemistry/ and information structures, drug information, and toxi- management al- cology searches and provides chemis- lows her to search try resources seminars to chemistry-fo- locate accurate cused groups within NIH. Recently, Marti Welch and the design Lany Keefer’s NCI-Frederick lab group: (sitting, left to right) compound proper- Brandys started to work on Joseph Hrabie, Larry K. Keefer, Joseph Saavedra; (standing, left ties and make ex- and development of a new compound to right) Carlos Velazquez, Michael Citro, Daniela Andrei, pert contributions database for the Imaging Probe Devel- Geoffrey Lynn, Ana Maciag, and Harinath Chakrapani to the LCC website: opment Center. 12 November — December 2007 At Home in the IPDC and OTT osh Duberman has been an syntheses of certain complex dye mol- J informationist at the NIH Library ecules, thereby allowing our scientists since May 2005. He has a Masters in to choose the best method from these Library Studies and a bachelor’s de- multiple alternatives. This in turn gree in chemistry, with extensive in- saved us time, effort, and resources.” formation research experience in the Duberman acknowledged that his private sector, as well as experience continuing education, and especially as a working scientist in both govern- his study of fluorescence and dye ment and private laboratories. chemistry, made it possible for him to Duberman has several patents and provide the kind of in-depth informa- has written numerous articles for pro- tion services relevant to Griffiths’ fessional publications about the infor- group. Duberman has also conducted mation industry, searching techniques, chemical substructure patent searches, and information resources. His areas called Markush searches, in pursuit of Michael Walden of expertise and research include in- potential IPDC inventions. He gets around: InformationistJosh tellectual property, chemistry, biotech- Promoting the work of NIH chem- Duberman with (left) IPDC Director Gary nology, pharmaceutics, engineering, ists is the purview of Steven Ferguson, Griffiths at the NIH Library’s new online competitive intelligence and technol- director of the Division of Technol- catalog access station, and (below) . . . ogy transfer resources, and informa- ogy Development and Transfer tion-retrieval issues. (DTDT) of the Office of Technology Duberman often works with Gary Transfer (OTT). He and his staff, as well Griffiths, director of the Imaging Probe as students taking the popular FAES Development Center (IPDC), and his course Biomedical Business Develop- staff. An NIH core chemistry facility ment for Scientists, take advantage of set up as part of the NIH Roadmap for Duberman’s wealth of chemistry and in- Medical Research, the IPDC is dedi- formation research expertise. cated to the production of imaging Topics covered in Duberman’s office probes for all requesting intramural sci- and classroom presentations, Ferguson entists. said, include “patent searching” and Griffiths said, “We have been very “how to use public search engines to busy with multiple collaborations now find information on pharmaceuticals and ongoing with around a dozen institutes vaccines.” and centers, indicating the demand for Ferguson’s division is responsible for such agents here at NIH. A result of assessing the technology products mar- Michael Walden this is that we tend to perform synthe- ket. Approximately 200 products on the . . . with DTDT Director Steven ses across the full range of chemical market, mostly laboratory reagents, were Ferguson amidst a display of compositions, which is a very broad licensed by NILL About 20 are vaccines technology transfer successes at knowledge range indeed. Because of and therapeutics. The division uses out- OTT's Executive Boulevard site our mandate and our multiple project side law firms to conduct complete areas, we have unique, ongoing, and patent searches. To read more about infonnationists, visit important needs for excellent library Keeping informed about NIH Library the NIH website at ing to “decipher multiple patent and challenge is how to manage it, sort it, or Suzanne Grefsheim at (301) 496-2448 or PRAT Fellowship Applications DueJanuary 30, 2008 he NIGMS Pharmacology Research Associate (PRAT) pro support research in preceptors’ laboratories. Applicants must T gram is now accepting applications for positions to begin identify a preceptor in their application. Preceptors may be any October 2008. This competitive research fellowship program tenured or tenure-track scientist at NIH or FDA who has agreed supports training at NIH or FDA laboratories for postdoctoral to host the applicant. Applicants must be citizens or permanent candidates. The program focuses on training in the pharmaco- residents of the United States and have been at the NIH or FDA logical sciences and related research areas such as molecular for no more than one year at the time they submit their applica- pharmacology, signal-transduction mechanisms, drug metabo- tion. lism, immunopharmacology, chemistry and drug design, struc- Applications for the 2008 PRAT Fellowships will be accepted tural biology, endocrinology, bioinformatics, and neuroscience. through January 30, 2008. For more information or applica- PRAT fellowships are three-year appointments at competitive tion materials, contact the PRAT program assistant at (301) 594- salaries. Some supply and travel funds are provided to help 3583 or e-mail 13 The NIH Catalyst Graduate Students Present Their Research and Explore Their Options at NIH by Christopher Wanjek Nearly 250 graduate students from around the country—selectedfrom about 750 applicants—attended the second annual NIH National Graduate Student Research Festival October 1 1-12. They came here to learn about NIH and its potentialpostdoc positions and to present their research. The Catalyst took a closer look at two of the posters. Genomic Variants and Acyclovir Efficacy cyclovir is the drug of choice for the treatment of herpes vims Ahepatitis. Its efficacy, however, varies greatly among patients, a frustrating problem not uncommon in pharmacology. Cheryl Cropp and her colleagues at the University of California, San Francisco, are narrowing in on one possible reason—variants in the organic anion transporter OAT2 (SLC22A7). The group’s two- year detective work continues to reveal surprising twists. Cropp’s project has examined the DNA of 272 healthy volunteers in the Bay area. Earlier work revealed that OAT2 in the liver interacts readily with acyclovir. From the donated DNA, she found six variants of OAT2: four single- tons and two polymorphic variants. (These two polymorphic, nonsynonymous variants were found only among African American donors, a finding of possible significance to be investigated later, she said.) The OAT2 protein threads in and out of the cell membrane. One of the nonsynonymous variants, ThrllOIle, is located in the extracel- lular environment, and the other, Arg325Trp, is in the cytoplasm, perhaps interfering with the uptake and intracellular function of acyclovir, respectively. Cropp found that the variants reduce the uptake of acyclovir by 50 percent compared with the wild-type OAT2. The group continues to develop tags to trace acyclovir uptake and utilization and hopes to Christopher Wanjek increase its size. Cropp’s DNA sample work could lead to screening Cheryl Cropp for acyclovir use. Cropp has a doctorate in pharmacy and is in her final year of a Ph.D. program in pharmacogenetics. She was impressed by the opportunities for interaction and collaboration at NIH. During her visit to the Graduate Student Research Festival, she toured NEI facilities and realized a potential connection between her work and therapies to treat herpes-related eye diseases. 9 Body Fat and Mortality s humans across the globe continue to pack on extra A weight, researchers remain unsure how best to gauge the accompanying potential risk of diseases and death. Scott Keith and his colleagues at the University of Ala- bama in Birmingham have examined the relationship be- tween estimated total body fat (TBF) and mortality, and they compared this to other obesity biomarkers, such as body-mass index (BMI), percent fat, and waist circumfer- ence. Keith utilized bioimpedance analysis measurements in the NHANES III database. BMI—weight in kilograms divided by squared height in meters—is the most common measure of obesity, adopted by the World Health Organization, the United Nations, and other international bodies. But BMI is limited as a health- risk predicter. For example, higher BMI in women appears to confer a greater risk of death than in men; and certain ethnic groups, such as southeast Asians, can maintain BMIs associated with being overweight but remain healthy. Ear- lier studies have shown that various measures of obesity and body fat yield inconsistent mortality risk results. Christopher Wanjek tool for predict- Scott Keith Keith found that TBF is a more powerful ing mortality risk than BMI and other measures, particularly because TBF is independent of sex. Waist circumference, however, is a strong predictor of mortality risk in women. He also found that percent fat (TBF divided by weight in kilograms) and TBF index (TBF divided by squared height in meters) were not interchangeable with TBF in terms of predicting mortality risk. While noting that more research is needed, he said that TBF might soon be used to complement the widespread use of BMI. Keith is in his final year of a doctorate program in biostatistics. His research has involved developing and applying statistical methodology to analyze medical and epidemiological data. “Opportunities [at NIH] are more advantageous than I’d predicted,” he said during his visit to the festival. 9 14 November — December 2007 On Tenure Track Carmen Williams joined the NIEHS in September, where she heads the Reproductive Medicine Group in the Labora- tory of Reproductive and Developmental Toxicology. Her lab has two major interests. One is the regulation of endometrial function, which is relevant to infertility as well as endometriosis and endometrial cancer. The other is the study of gametes and preimplantation embryos to better un- derstand infertility and to provide information relevant to contraceptive development. Her past research on these topics—while holding various titles at the University of Pennsylvania in Philadelphia, from infertility fellow to assistant professor—mainly used mouse models. Her lab now also uses human sperm and en- dometrium samples. As a self-described fertility doc with a doctorate in cell biology, Williams said she hopes to serve as an information resource on women’s reproductive health for the NIH intramural staff. A key protein involved in implantation in the mouse is Wei Li epithelial membrane protein-2 (EMP2), a Wei Li joined the Unit of Retinal Physiology, NEI, in August molecular facilitator 2007. He began his study of the physiology and circuitry of thought to organize the mammalian retina as a postdoctoral fellow in Chicago in other proteins into the Northwestern University laboratory of Steven DeVries, cell surface signal- where he focused on the cone photoreceptors in the retina ing complexes, al- and their associated neurons. tering the adhesive- Mammalian vision begins with two types of light-sensing ness of the endo- neurons—rods, which function predominantly in low-light con- metrium. ditions, and cones, which function in daylight and are re- EMP2 localizes on sponsible for color vision. Both receive visual signals and the surface of the send them on to the retinal neurons and ultimately to the uterine epithelium brain. One research avenue Li is pursuing at NEI is determin- at the time of im- ing how retinal neurons are wired and how they function. plantation, and re- Using direct synaptic stimulation or natural-light stimula- duced amounts tion to take recordings from neurons, and combining these hinder implantation. with anatomical connections, Li hopes to determine how these Conversely, a higher visual cues are processed in the retina and passed to the higher expression of EMP2 visual centers of the brain. is seen in poor- Most mammals, including humans, have rod-dominated reti- prognosis endome- nas; but the ground squirrel—Li’s model organism—is unique trial cancer, the most in that its retina is composed predominantly of cone photore- common gyneco- ceptors, allowing him to address more specific questions of logic cancer in the mammalian color vision. United States. Will- primates have a trichromatic (blue-green- Carmen Williams Humans and some iams is collecting red) system of cones; most other mammals have only a blue- endometrial biopsies from women with and without fertility green cone system. Li is especially interested in elucidating problems to futher examine the role of EMP2 in infertility the neural connections and and signaling process of the blue and endometriosis. cones, which are the most evolutionarily conserved but least As for male infertility, Williams said that surprisingly little well understood. was known before 2002 about how a sperm fertilizes an Li is also using his ground squirrel model to examine de- egg. Then a British group identified a key sperm molecule, generation and photoreceptor-protection mechanisms. Dur- phospholipase C-C, (PLCQ, which initiates calcium oscilla- ing a squirrel’s hibernation, retinal neurons undergo degen- tions required for fertilization when sperm enters egg. erative-like changes, including detachment of the photore- Williams’ group demonstrated how this molecule is bio- ceptor synaptic component from the membrane and retrac- logically significant in mice. Because a repetitive pattern of tion of neuronal structures. Once the squirrel comes out of calcium oscillations is required for successful pre- and hibernation, however, the retina completely recovers within postimplantation development, suboptimal PLC(, function five days. could explain some cases of infertility, Williams said. This hibernation scenario, Li says, provides a unique win- If this hypothesis is correct, she envisions a test to identify dow into natural photoreceptor-protection mechanisms in couples who would benefit from treatment of this defect. adverse environments. In addition, these studies offer a sys- “There is a huge gap in our understanding of male infertil- tem in which to study synaptic regeneration and prevention ity," Williams said. of further degeneration after retinal damage. — Christopher Wanjek — Yvonne Evrard 15 People Recently Tenured Montserrat Garcia-Closas received an In addition, I am collaborating with (NAT2) slow acetyl ator and glutathione M.D. degree from the University of two efforts to identify genetic suscepti- 5-transferase null genotype with in- Barcelona in Spain in 1990 and an bility markers through genome-wide as- creased risk of bladder cancer. M.P.H. in quantitative methods and a sociation studies (GWAS) at the Univer- The data also supported an interac- Dr.P.H. in epidemiology from the sity of Cambridge, U.K., and the Cancer tion between smoking and NAT2 geno- Harvard School of Public Health in Genetic Markers of Susceptibility project. type, which is one of the few consistent respectively. 1993 and 1996, Shejoined Recent publications from these studies gene-environment interactions described the Hormonal and Reproductive Epide- have identified at least five novel ge- to date. In addition, I showed that com- miology , in as netic susceptibility in Branch , NCI 1996 a markers for breast mon variants the nucleotide excision postdoctoralfellow and is now a senior cancer. Numerous other variants are repair pathway are likely to alter blad- investigator in that branch. likely to be identified in the coming der cancer risk. I am interested in the appli- years using this approach. More recently, we used a highly multi- cation of biomarkers in mo- Ongoing work after the plexed genotyping platform to explore lecular epidemiologic studies initial identification of mark- associations between variants in cancer- of breast, ovarian, endometrial, ers includes: related genes and bladder cancer, which and bladder cancers, with spe- a Fine mapping and func- resulted in the identification of novel cial emphasis on the study of tional studies to identify genes that may be involved in bladder genetic susceptibility and etio- causative markers cancer etiology. logic heterogeneity of breast B Evaluation of how I plan to follow up on findings from cancer. lifestyle factors affect the our candidate gene investigations in the I have also conducted a se- risk from genetic variants recently formed International Consor- ries of methodological inves- B Learning how different tium of Bladder Cancer Study. In addi- tigations to address relevant genetic variants interact with tion, we are planning to carry out a Montserrat Garcia- scientific questions derived other in affecting risk of bladder cancer in collabora- Closas each GWAS from molecular epidemio- a Learning whether ge- tion with other intramural and extramu- logic studies such as assessment of false- netic variants are differentially associ- ral studies. positive findings, collection and use of ated with different types of breast can- buccal cell DNA, and creation of pilot cer with different clinical and pathologic Kent Hunter received hisPh.D. in biol- studies for biomarker development. features at presentation ogy from the Massachusetts Institute of The discovery of susceptibility genes B Learning how variants affect survival Technology> in Cambridge in 1991 He for cancer holds great promise for im- My work related to etiologic hetero- was an associate member at the Fox Chase proving risk assessment and developing geneity of breast cancer in the Polish Cancer Center in Philadelphia before targeted preventive strategies. It also pro- breast cancer study has demonstrated joining the laboratory ofPopulation Ge- vides an opportunity to dissect the com- substantial heterogeneity in breast can- netics. NCI in 1999 . He is cu rrently a se- plex etiology of each cancer. cer risk factors by histopathological tu- nior investigator in the Laboratory ofCan- The importance of susceptibility genes mor characteristics of clinical relevance, cer Biology and Genetics, NCI. in risk assessment is being evaluated in particularly tumor grade and size. The focus of my laboratory is the study the Polish Breast, Ovarian, and Endome- In this study, we are using of inherited metastasis sus- trial Cancer studies, a set of parallel, mo- tissue microarray blocks to ceptibility in breast cancer. lecular epidemiologic studies targeting obtain standardized, rapid, Previously, metastasis was these three tumors in women and includ- and cost-effective immuno- thought to be the result of ing about 2,500 breast, 500 endometrial, histochemical characteriza- sequential random somatic and 300 ovarian cancer cases and more tion of many tumors. This alterations that occurred in than 2,500 control subjects. This com- process allows us to evalu- tumor cells as tumors plex study combines detailed exposure ate relationships between tu- evolved. Thus, metastatic assessment and comprehensive collec- mor markers with known disease was was viewed as tion of biological specimens. breast cancer risk factors and a random process, whose In exploring genetic susceptibility of newly discovered genetic appearance could not be breast cancer, I have evaluated variation markers. predicted before the devel- in genes in several candidate pathways, I have also worked on the opment of the primary tu- including DNA repair, apoptosis, and evaluation of genetic suscep- mor. regulation of telomeres. tibility factors for bladder cancer and the While somatic mutation is clearly a With the Breast Cancer Association interaction of those factors with envi- part of metastatic progression, work in Consortium, a consortium of studies in- ronmental and occupational exposures. my laboratory has demonstrated that cluding more than 20,000 breast cancer Because of the central role of tobacco there is also a significant inherited pre- cases, we were able to uncover convinc- smoking in bladder carcinogenesis, I ini- disposition to developing secondaiy tu- ing evidence for modest associations tially focused on polymorphisms in mors. Using a highly metastatic mouse between breast cancer risk and two com- genes involved in carcinogen metabo- mammary tumor model and a simple mon genetic variants, caspase 8 (CASP8 lism and DNA repair. Data from this breeding scheme, we demonstrated that D302H) and transforming growth factor- study provided compelling evidence for the genetic background upon which the 13 1 (TGFB1 LI OP). the associations of TV-acetyltransferase 2 primary tumor arose had a significant 16 - _ November — December 2007 impact on the number of subsequent L. Aravind (aka Aravimd Iyer) received erating a complete natural classification lung metastases. bisPh.D. in 1999from Texas A&M Uni- of the protein universe. These results suggest that in addition versity, College Station. He worked as a Our studies on the next level of bio- to the somatic mutations, activating or staff scientist at NCBI from December logical organization have followed the inactivating specific genes that have been 1 999 to December 2002 and is currently evolutionary trajectories of entire func- previously studied in metastatic disease, senior investigator in the Computational tional systems involved in RNA and DNA polymorphisms that subtly effect gene Biology Branch, NCBI. metabolism, apoptosis, function also play an important role in I am an evolutionary biolo- ubiquitin signaling, transcrip- breast cancer progression. gist, and I use computational tional control, and chroma- Using an integrated genomic and com- methods to decipher biologi- tin-level regulation. plex trait genetic mapping strategy, my cal functions from genome More recently, we have in- lab has begun to identify some of the sequences. vestigated how whole bio- genes that may contribute to metastasis The past decade has been logical networks, especially susceptibility. The first gene we identi- an exciting and definitive pe- those involved in transcrip- fied is the signal transduction regulator riod in modern biology. tion, evolve as their compo- signal-induced proliferation-associated Thanks to the advances in se- nent nodes undergo diversi- gene Sipal. quencing technology, we are fication. We identified an amino-acid polymor- in possession of the genome Especially striking is our phism in this protein in mice that re- sequences of not just hu- finding that despite conser- duces its enzymatic function. Modeling mans, but organisms span- vation of target genes, the the effect of this polymorphism by halv- ning the entire tree of life. With the major specific transcription factors are ing the endogenous levels of Sipal whole script of an organism’s biology subject to massive lineage-specific dis- mRNA significantly reduced the meta- spread before us, we are ready to ob- placement via new innovations. Differ- static capacity of a highly malignant tain unprecedented glimpses of life’s ent lineages may therefore differ dramati- mammary tumor cell line, suggesting workings. However, to apprehend these cally in their transcription factors despite that subtle variations in this gene’s ac- views, we need to be effective readers retaining a similar complement of target tivity may play a role in human breast and interpreters of this script. genes, suggesting that the evolutionary cancer progression. My group has primarily worked to- turnover in transcription factors is a ma- In addition to the mouse modeling wards this objective, developing and jor player in phenotypic diversity. experiments, we have also performed using computational methods for com- Our genome-scale analysis has led to pilot epidemiology experiments to di- paring protein sequences and structures the understanding of several aspects of rectly investigate SIPA1 in humans. In and analyzing biological networks. biology at the organismal level, such as collaboration with Hoda Anton-Culver at To obtain a reasonably complete ap- the parasitic adaptations of apicom- the University of California at Irvine, we proximation of biological function, my plexans and large DNA viruses, the ori- demonstrated that polymorphisms in group investigates different evolution- gins of eukaiyotic cellular complexity, SIPA1 were associated with markers of ary problems at multiple organizational and sensory and signaling strategies of poor outcome in humans, consistent levels. At the “microscopic” level, we organizationally complex bacteria. with our hypothesis that this gene may study protein domains in order to iden- In particular, we have made several be one of the factors that establish meta- tify their structural and functional de- efforts toward understanding the biol- static susceptibility in humans. terminants. At the “mesoscopic” level, ogy of apicomplexans parasites, which There are several important implica- we study the various interactions be- are causative agents of malaria, toxoplas- tions of our research. First, our work tween different proteins or proteins and mosis, a fatal lymphoma in cattle, and suggests that modulating gene function nucleic acids in the context of entire cryptosporidiosis. We computationally by relatively minor amounts may have biological functional pathways. Finally, predicted novel O-linked protein glyco- significant impacts on cancer progres- at the “macroscopic” level we attempt sylation pathways that are likely to sion. to reconstmct salient aspects of organismal modify surface molecules and play a This possibility leads to the further biology from whole genome sequences. critical role in the way these parasites hypothesis that one may subtly change Our studies at the microscopic level interact with their host. the molecular state of the cell, rather than have strongly focused on the discoveiy Our discovery of apicomplexan-spe- use a cytotoxic agent, to prevent relapse of new protein domains and the gen- cific transcription factors has also pro- in breast cancer patients. eration of testable hypotheses regard- vided a means to unravel the hitherto Moreover, the existence of polymor- ing their functions. unknown mechanisms of gene regula- phisms in the germline DNA that estab- Some of our major findings include tion in these organisms. lish susceptibility to metastatic progres- the computational discovery of new In conclusion, we hope to continue sion should enable the development of peptidases involved in deubiquitination; to exploit computational methods and a blood-based prognostic test to iden- proteins involved in viral and cellular evolutionary principles to arrive at a de- tify those patients at risk for dissemi- DNA packaging and segregation; and finitive understanding of the major bio- nated disease. We hope that this test will novel enzymes and factors involved in logical systems. This in turn would pro- ultimately result in better tailored treat- chromatin dynamics, RNA modification, vide vital insights regarding normal as ment for patients, reducing the number and post-transcriptional gene silencing. well as disease states in humans and of relapses and cancer-related deaths. Overall, we are moving toward gen- other organisms. 17 Recently Tenured Zu-Hang Sheng received his Ph D. from large portion of axonal mitochondria in Given that defects in axonal transport the University of Pennsylvania in Phila- stationaiy state through an interaction with of presynaptic cargos and mitochondria delphia in 1993 He completed his the microtubule-based cytoskeleton. The in neurons have been implicated in the postdoctoral training in neuroscience at deletion of the snph gene in mice dramati- pathogenesis of neurodegeneration, our the University of Washington, Seattle, be- cally increases mitochondrial motility, re- studies will yield fundamental information fore he came to N1NDS as a tenure-track duces their density in axons, and conse- that may have an impact on the under- investigator in 1997. He is currently a se- quently influences short-term facilitation standing of human neurodegenerative dis- nior investigator and chiefofthe Synaptic during prolonged high-frequency stimu- orders. Function Section, NINDS. lation, probably by affecting Our research is focused on calcium dynamics at presyn- Yihong Yang received his Ph.D. degree molecular and cellular mecha- aptic boutons. in biophysicsfrom the University ofIllinois nisms underlying (1) the ax- Our studies elucidate a at Urbana-Champaign in 1995, under the onal transport of synaptic com- mechanism underlying the supervision of Nobelist Paul Lauterbur, ponents and organelles essen- docking of axonal mitochon- who invented magnetic resonance imag- tial for the assembly of syn- dria and provide evidence that ing (MR1). He did postdoctoral work at apses, and (2) the regulation the increased motility and/or N1H in the Laboratory ofDiagnostic Radi- of synaptic vesicle (SV) prim- reduced density of axonal mi- ology Research from 1995 to 1998 and ing for fusion. Such mecha- tochondria have a significant then became an assistant professor in the nisms are crucial for the initial impact on presynaptic func- Functional Neuroimaging Laboratory at establishment of presynaptic tion. the Weill Medical College of Cornell Uni- terminals and for the modula- Fran Pollner We initially identified versity in New York before joining the Zu-Hang Sheng tion of synaptic function. syntabulin as a syntaxin-bind- Neuroimaging Research Branch, NLDA, in We initially identified Snapin ing and KIF5B motor-adaptor 2002 as an investigator. He is currently a as a SNAP-2 5-binding protein. The physi- protein that mediates anterograde trans- senior investigator and chief of the MRL ological role of Snapin in SV exocytosis port of syntaxin-1 to neuronal processes. Physics Section in that branch. was examined and further confirmed by Recently, we showed that the MRI and spectroscopy are microinjection or overexpression of Snapin syntabulin-KIF5B transport noninvasive, versatile tech- in presynaptic neurons in culture and by complex plays a critical role in niques that are ideal for pro- overexpression of Snapin in hippocampal axonal delivery of the active viding system-level informa- neurons. zone (AZ) components essen- tion on humans and animals. Our studies using snapin-knockout mice tial for presynaptic assembly. My research at NIDA has fo- in combination with genetic rescue experi- Using time-lapse imaging in cused on the development of ments provide evidence that Snapin modu- live hippocampal neurons, we advanced magnetic resonance lates neurosecretion in chromaffin cells by demonstrate that syntabulin co- techniques to study brain stabilizing the structural coupling of the migrates with AZ precursor structure, function, and me- calcium sensor synaptotagmin-I to the vesicles along axonal pro- tabolism, particularly as they i vesicle fusion machinery SNARE complex, cesses. The knockdown of are related to the effects of a critical step for priming docked vesicles syntabulin or interference of its Yihong Yang substance abuse on the brain. for fusion. The deletion of Snapin leads interactions with either KIF5B My group has developed to a marked reduction in the amount of or syntaxin-1 in developing neurons re- novel functional MRI (fMRI) methods with synaptotagmin-I-SNARE complex and de- sults in the deficient trafficking of the AZ enhanced detection and quantification fective exocytosis in the snapin (-/-) chro- components to nerve terminals, reduces power to observe brain activation elicited maffin cells. the density of release sites, impairs syn- by cognitive tasks or administration of Individual SNAREs are distributed to aptic transmission, and inhibits the activ- daigs. specific membrane compartments along ity-induced formation of new presynaptic These fMRI techniques are able to mea- secretory and endocytic pathways and boutons. sure multiple functional signals simulta- contribute to the specificity of membrane Our findings suggest a mechanism neously (for example, cerebral blood flow, trafficking. In addition to its association through which long-term presynaptic plas- blood volume, and blood oxygenation) with SVs, our ongoing study suggests that ticity is regulated by the syntabulin-KIF5B- and to quantify local oxygen consump- Snapin is also involved in an endosome- mediated axonal transport of the AZ com- tion in the brain. Neuronal activity accom- lysosome trafficking pathway, possibly ponents, thus contributing to the activity- panied by metabolism can then be sepa- through interactions with endosomal induced presynaptic assembly. rated by potential vascular artifacts in neu- SNAREs. I believe that our continued application ropharmacological studies using the com- Syntaphilin (SNPH) is a neuron-specific of these multidisciplinary systems analy- prehensive information provided by these protein initially identified as a candidate sis of genetically engineered mice will techniques. inhibitor of presynaptic function. We re- contribute to an understanding of the We have conducted research on func- cently generated mouse mutants with a molecular mechanisms that are crucial for tional connectivity of the brain using “rest- homozygous deletion for the snph gene, regulation of activity-dependent presyn- ing-state” fMRI, in which intrinsic interac- leading to the discovery of a novel role aptic plasticity by (1) the anterograde ax- tions between brain regions are reflected for SNPH as a docking receptor of axonal onal transport of presynaptic components, by synchronized fluctuations of the fMRI mitochondria. (2) the axonal mitochondrial trafficking signals. Our findings indicate that SNPH is tar- and docking, and (3) the priming and regu- Compared with healthy control subjects, geted to and required for maintaining a lation of SV exocytosis. cocaine users showed significant reduc- 18 November — December 2007 Demystifying Medicine for Ph.D.s, 2008 When: every Tuesday fromJanuary 8 to May For academic credit, register with FAES: 13, 4:00 to 6:00 p.m. Date Speakers Subjiect tion of functional connectivity in the “re- January ward circuitry” of the brain, which was heavily involved in addiction processes. John Coffin (NCI) HIV/AIDS: the ultimate This study revealed for the first time the 8 Henry Masur (CC) chameleon relationship between functional brain con- Heart failure: advances nectivity and chronic drug abuse, and Michael Sack (NHLBI) regarding a major clinical pointed to a powerful new tool to study 15 Bob Balaban (NHLBI) problem drug-induced neuronal dysfunction or dysregulation. Meral Gunay-Aygun (NHGRI) Cystic diseases and cilia: a 22 Magnetic resonance spectroscopy (MRS) Carolyn Ott (NICHD) new frontier can be used to measure metabolite and Harvey Klein (CC) Diseases from the blood neurotransmitter concentrations in vivo. 29 Harvey Alter (CC) bank: progress and the future My group has developed a new MRS method that provides well-resolved February glutamate, glutamine, and GABA signals. We performed MRS experiments on co- Warren Strober, Inflammatory bowel 5 NIDDK caine users and healthy control subjects Peter Mannon, .MAID disease: what is the target? that revealed significantly lower glutamate Malaria: big killer and big levels in the anterior cingulate cortex of Thomas Wellems (NIAID) 12 advances the cocaine addicts, a finding potentially John Robbins (NICHD) associated with chronic drug addiction. Nora Volkow (NIDA) Hunger, appetite, obesity, We have also developed several new 19 Monica Skarulis (NIDDK) addiction: the new pandemic diffusion-based MRI methods for better delineating complex brain white matter Abner Notkins (NIDCR) Diabetes and autoimmunity: 26 structures. These methods can be used to Phillip Gorden (NIDDK) turning against self improve fiber-tracking techniques by iden- March tifying multiple fibers coexisting in an im- age voxel not possible with traditional Amy Agrawal (CC) West Nile virus: a new threat — 4 diffusion tensor imaging. Using a group- Philip Murphy (NIAID) level analysis on diffusion-based imaging Les Biesecker Genetic screening: finding data, we assessed structural integrity of (NHGRI) 11 Mendelian disease genes neural circuits relevant to drug addiction. Julie Sapp (NHGRI) Recently, we developed an animal Andrew Singleton (NIA) Neurologic diseases in the model to investigate the underlying mecha- 18 Katrina Gwinn-Hardy (NINDS) genome era nisms of resting-state fMRI by integrating electrophysiological and fMRI signals in Cystic fibrosis: a common 25 Francis Collins (NHGRI) the resting rat brain. inheritable disease with Sharon Milgram (OD) Our results demonstrated that, unlike the many unknowns evoked fMRI response that correlated with power changes in high-frequency bands, April power coherence in low-frequency bands William Gahl, Marjan (particularly the delta band) correlated with 1 Huizing, Amanda Helip- Lysosomal diseases: patients the resting-state fMRI signal in a region- Wooley, Wendy Westbroek and problems specific and anesthesia dose-dependent (NHGRI) fashion. These results provided new insights into Ellen Sidransky (NIMH) Gaucher’s disease: treating a the linkage between neuronal activity and 8 Chris Austin (NHGRI) genetic disease hemodynamic-based fMRI signal at rest. Leighton (CC) Traumatic brain injury: Most existing fMRI techniques measure Chan treatment neuronal activity indirectly through hemo- 15 Walter Koroshetz (NINDS) mechanisms, and dynamic responses coupled to neuronal and DOD colleagues challenges and metabolic changes. To avoid poten- Howard Fine (NCI) Brain cancer: problems and 2+- 22 tial vascular effects of drugs, we used Mn and colleagues progress enhanced MRI to detect neuronal activity reflected by an influx of Ca 2+ ions due to Liver cancer: a global prob- Ezekiel Emanuel (CC) action potentials. 29 lem. Who gets THE liver Win Arias (NICHD/OD) In experiments on rats given cocaine, transplant? we that this noninvasive method showed May detected brain activations as consistently as nonhemodynamic invasive methods and Giuseppe Giaccone (NCI) Lung cancer: clinical thus appears to be a very promising tool 6 Lyuba Varticovski (NCI) progress and the cancer for mapping drug-induced neuronal activ- stem cell paradigm ity. H 13 Finale: Minisymposium: What does the future hold for Ph.D.s ? TBA 19 The NIH Catalyst Catalytic Coined Federal Cato^afon KRfcoff Reactions? fo +#»e Cowboy Two-S+ef> f you have a photo or I other graphic that reflects an aspect of life at NIH (including laboratory life) or a quotation that scientists might appreciate that would be fit to print in the space to the right, why not send it to us via e-mail: [email protected]>; fax: 402-4303; or mail: Building 2, Room 2E26. 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