DOCSLIB.ORG

Pax-6,A Murine Paired Box Gene, Is Expressed in the Developing

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Pax-6,A Murine Paired Box Gene, Is Expressed in the Developing Development ID, 1435-1449 (1991) 1435 Printed in Great Britain © The Company of Biologists Limited 1991 Pax-6, a murine paired box gene, is expressed in the developing CNS CLAUDIA WALTHER and PETER GRUSS Max Planck Institute for Biophysical Chemistry, Department of Molecular Cell Biology, Gtittingen, Germany Summary A multigene family of paired-box-containing genes (Pax of the forebrain and the hindbrain. In the neural tube, genes) has been identified in the mouse. In this report, expression is mainly confined to mitotic active cells in the we describe the expression pattern of Pax-6 during ventral ventricular zone along the entire anteroposterior embryogenesis and the isolation of cDNA clones span- axis starting at day 8.5 of development. Pax-6 is also ning the entire coding region. The Pax-6 protein consists expressed in the developing eye, the pituitary and the of 422 amino acids as deduced from the longest open nasal epithelium. reading frame and contains, in addition to the paired domain, a paired-type homeodomain. Beginning with Key words: paired box, homeobox, Pax, CNS day 8 of gestation, Pax-6 is expressed in discrete regions development, eye development, embryogenesis. Introduction gsb-d paired box, a murine multigene family of paired- box-containing genes (Pax genes) of to date eight The fruit fly Drosophila has proved a powerful model members has been isolated (Deutsch et al. 1988; for deciphering the complex genetic program underly- Dressier et al. 1990; Plachov et al. 1990; Jostes et al. ing development. A large number of developmental 1991; Goulding et al. 1991; Walther et al. 1991). All Pax control genes of Drosophila have been isolated and genes described to date exhibit a temporally and genetically analyzed. These studies have revealed an spatially restricted expression pattern during embryo- array of hierachical and combinatorial interactions of genesis, compatible with a regulatory role in vertebrate their gene products that are required for controlling development. The Pax genes, with the exception of pattern formation and morphogenesis (for reviews see Pax-1, are expressed in the developing nervous system. Akam (1987); Scott and Carroll (1987); Ingham (1988)). Expression is detected along the entire anteroposterior Many of these genes contain conserved sequence motifs axis of the neural tube and the hindbrain where it is such as homeobox, zinc-finger motif, helix-loop-helix confined in the transverse plane to distinct regions. Pax- motif and paired box and these in turn have been used 3 transcripts are already detected at day 8.5 of gestation to isolate potential developmental control genes from a and are restricted to mitotic cells in the dorsal half of variety of vertebrate species (for review see Scott et al. the neural tube, the alar and roof plate (Goulding et al. (1989); Kessel and Gruss (1990)). Like their Drosophila 1991). Pax-7 shows a similar expression pattern except counterparts, many of these vertebrate genes appear to that it is not expressed in the most dorsal part of the play a role in controlling pattern formation and neural tube (Jostes et al. 1991). Pax-2 and Pax-8 are morphogenesis during development (Kessel et al. 1990; expressed later in neurogenesis beginning with day 10 Wright etal. 1989). and day 11 of gestation, respectively. Transcripts are The paired box was originally discovered in the detected in discrete subpopulations of postmitotic cells Drosophila segmentation genes paired, gooseberry- within the alar and basal plate (Nornes et al. 1990; distal (gsb-d) and gooseberry-proximal (gsb-p) (Bopp et Plachov et al. 1990). al. 1986; Baumgartner et al. 1987) and subsequently in The Pax genes were cloned on the basis of their two developmental^ regulated tissue-specific genes of homology to a sequence motif found in segmentation Drosophila, Pox neuro and Pox meso (Bopp et al. genes of Drosophila, which are involved in building the 1989). The paired box has been highly conserved during metameric body plan. Segmentation is also an import- evolution, being present in such divergent organisms as ant feature of vertebrate embryogenesis (Hogan et al. nematodes, zebrafish, Xenopus, chicken and man 1985) and all the Pax genes described to date are (Dressier et al. 1988; Burn et al. 1989). It encodes a expressed in segmented structures such as the differen- protein domain of 128 amino acids which has been tiating somites or the developing excretory system. In shown to be a novel DNA-binding motif (Treisman et the mouse, however, paired-box-containing genes do al. 1991; Chalepakis etal. 1991; Goulding etal. 1991). not seem to be involved in the generation of segmental Based on sequence homology to the Drosophila structures but rather in their differentiation since 1436 C. Walther and P. Gruss expression begins only after these structures have DNA sequence analysis already formed (Deutsch et al. 1988; Dressier et al. Overlapping subclones of the Pax-6 cDNA clones were 1990; Plachov et al. 1990; Jostes et al. 1991; Goulding et generated in M13 mpl8 and mpl9 vectors. Single-stranded al. 1991). DNA was prepared and sequenced with the dideoxy method The potential developmental importance of members (Sanger et al. 1977) using either Sequenase (US Biochemicals) of the Pax gene family is further highlighted by the or T7 kits (Pharmacia). Computer analysis of the sequence correlation of a Pax gene with the developmental was performed using the GCG program package (Devereux et al. 1984). mutant undulated (un). Beginning with day 9 of gestation, Pax-1 is expressed in the sclerotome of the differentiating somites and at later stages in the Northern analysis intervertebral discs anlagen of the developing vertebral Embryos were obtained from natural matings of female column. A point mutation in the Pax-1 gene causing a NMRI and male C57BL/6 mice and the day of the vaginal reduction of DNA-binding affinity (Chalepakis et al. plug was designated day 0.5. Tissues were isolated from adult female NMRI mice. Embryos and tissues were frozen in liquid 1991) disturbs the normal development of the vertebral nitrogen, homogenized in guanidinium thiocyanate (Chirgwin column and was shown to be the cause for the un et al. J;979)'ahd poly(A)+ RNA was prepared using oligo(dT)- phenotype (Balling et al. 1988). cellulose columns according to Ausubel et al. (1987). Samples In this report, we present the isolation of cDNAs containing approximately 10 ug of denatured poly(A)+ RNA encompassing the complete coding region of the Pax-6 were electrophoresed on 1% agarose/formaldehyde gels, protein and a detailed analysis of the expression pattern transferred to Hybond-N membranes using IOXSSC and of Pax-6 during embryogenesis. Pax-6 is another crosslinked under UV light. The filters were hybridized with the random oligo-labeled (Feinberg and Vogelstein, 1983) member of the murine paired-box-containing gene genomic HindUI fragment of Pax-6 (see screening of cDNA family, which however encodes a rather divergent libraries) under the following conditions: 7.5% dextran paired domain and paired-type homeodomain. The sulfate, 5xSSC, 5xDenhardts, 50% formamide (Fluka), 1 % expression pattern of Pax-6 also differs in several SDS, 10mM Tris-HCl pH7.5, 0.1 mM sodium pyrophosphate, aspects. Unlike other Pax genes, Pax-6 is not expressed 0.1 mM ATP and 0.1 mgml"1 denatured salmon sperm DNA in segmented mesodermal structures. Pax-6 also is the at 65°C for at least 16h. Filters were washed in 2xSSC, 1 % first Pax gene described to be expressed in the ventral SDS at 65°C, followed by two washes in O.lxSSC, 0.1 % SDS neural tube before neural differentiation starts. The at 65°Cfor30min. expression pattern of Pax-6 in the neural tube is compatible with a role for Pax-6 in the regional In situ hybridization specification of cells in the neural tube with respect to Radioactive RNA probes were generated by in vitro the dorsal-ventral axis. Transcripts of Pax-6 are also transcription from a linearized plasmid clone containing an present in distinct regions of the developing brain, but •EcoRl-AT/eZ-cDNA-fragment encoding most of the 3' part in contrast to Pax-3 and Pax-7, the overall spatial of the Pax-6 paired box (see Fig. 1) using 100 /*Ci 35S-CTP and distribution of transcripts remains essentially the same T3 or T7 RNA polymerases (Pharmacia). After DNAase throughout development. Furthermore, Pax-6 is ex- digestion, probes were extracted with phenol and chloro- pressed in the developing pituitary, the olfactory form/isoamylalcohol and precipitated 3x with ammonium epithelium and in the developing eye in a pattern acetate. The probes were resuspended in 50% formamide, 10 mM DTT. suggestive of a regulatory role for Pax-6 in the Sections were prepared and hybridized essentially as development of the main structures of the eye. described (Hogan et al. 1986; Dony and Gruss, 1987) with some minor modifications. Sections (8/xm) were cut with a cryostat at -20°C and transferred onto slides subbed with gelatine and chrome alum. Sections were dried at 50°C, fixed in 4% paraformaldehyde (PFA) for 20min, rinsed with PBS Materials and methods and dehydrated in a graded ethanol series. Slides were air dried and stored at — 20°C until hybridized. Prior to Screening of cDNA libraries hybridization, sections were rehydrated in distilled water and Approximately 1.5 xlO6 clones of a AgtlO cDNA library incubated at 70 °C in 2xSSC for 30min. The following steps prepared from 8.5 day p.c. mouse embryos (Fahrner et al. were done at room temperature. After a second rinse with 1987) and 8X105 clones of a AgtlO cDNA library prepared water, sections were digested with 0.125 mg ml""1 pronase for from 11.5 day embryos (Clontech) were transferred to lOmin.
Load more

Recommended publications
  • Functional Analysis of the Homeobox Gene Tur-2 During Mouse Embryogenesis
    Functional Analysis of The Homeobox Gene Tur-2 During Mouse Embryogenesis Shao Jun Tang A thesis submitted in conformity with the requirements for the Degree of Doctor of Philosophy Graduate Department of Molecular and Medical Genetics University of Toronto March, 1998 Copyright by Shao Jun Tang (1998) National Library Bibriothèque nationale du Canada Acquisitions and Acquisitions et Bibiiographic Services seMces bibliographiques 395 Wellington Street 395, rue Weifington OtbawaON K1AW OttawaON KYAON4 Canada Canada The author has granted a non- L'auteur a accordé une licence non exclusive licence alIowing the exclusive permettant à la National Library of Canada to Bibliothèque nationale du Canada de reproduce, loan, distri%uteor sell reproduire, prêter' distribuer ou copies of this thesis in microform, vendre des copies de cette thèse sous paper or electronic formats. la forme de microfiche/nlm, de reproduction sur papier ou sur format électronique. The author retains ownership of the L'auteur conserve la propriété du copyright in this thesis. Neither the droit d'auteur qui protège cette thèse. thesis nor substantial extracts fkom it Ni la thèse ni des extraits substantiels may be printed or otherwise de celle-ci ne doivent être imprimés reproduced without the author's ou autrement reproduits sans son permission. autorisation. Functional Analysis of The Homeobox Gene TLr-2 During Mouse Embryogenesis Doctor of Philosophy (1998) Shao Jun Tang Graduate Department of Moiecular and Medicd Genetics University of Toronto Abstract This thesis describes the clonhg of the TLx-2 homeobox gene, the determination of its developmental expression, the characterization of its fiuiction in mouse mesodem and penpheral nervous system (PNS) developrnent, the regulation of nx-2 expression in the early mouse embryo by BMP signalling, and the modulation of the function of nX-2 protein by the 14-3-3 signalling protein during neural development.
    [Show full text]
  • Perspectives
    Copyright 0 1994 by the Genetics Society of America Perspectives Anecdotal, Historical and Critical Commentaries on Genetics Edited by James F. Crow and William F. Dove A Century of Homeosis, A Decade of Homeoboxes William McGinnis Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520-8114 NE hundred years ago, while the science of genet- ing mammals, and were proposed to encode DNA- 0 ics still existed only in the yellowing reprints of a binding homeodomainsbecause of a faint resemblance recently deceased Moravian abbot, WILLIAMBATESON to mating-type transcriptional regulatory proteins of (1894) coined the term homeosis to define a class of budding yeast and an even fainter resemblance to bac- biological variations in whichone elementof a segmen- terial helix-turn-helix transcriptional regulators. tally repeated array of organismal structures is trans- The initial stream of papers was a prelude to a flood formed toward the identity of another. After the redis- concerning homeobox genes and homeodomain pro- coveryof MENDEL’Sgenetic principles, BATESONand teins, a flood that has channeled into a steady river of others (reviewed in BATESON1909) realized that some homeo-publications, fed by many tributaries. A major examples of homeosis in floral organs and animal skel- reason for the continuing flow of studies is that many etons could be attributed to variation in genes. Soon groups, working on disparate lines of research, have thereafter, as the discipline of Drosophila genetics was found themselves swept up in the currents when they born and was evolving into a formidable intellectual found that their favorite protein contained one of the force enriching many biologicalsubjects, it gradually be- many subtypes of homeodomain.
    [Show full text]
  • REVIEW Cell and Molecular Biology of Notch
    459 REVIEW Cell and molecular biology of Notch Ulla-Maj Fiu´za and Alfonso Martinez Arias Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK (Correspondence should be addressed to U-M Fiu´za; Email: [email protected]) Abstract Notch signalling is a cell–cell communication process, which complexity which could account for the multitude of roles it has allows the establishment of patterns of gene expression and during development and in adult organisms. In this review, we differentiation, regulates binary cell fate choice and the will describe the multiple roles of Notch and how various factors maintenance of stem cell populations. So far, the data published can regulate Notch signalling. has elucidated the main players in the Notch signalling pathway. Journal of Endocrinology (2007) 194, 459–474 However, its regulatory mechanisms are exhibiting an increasing The structure of Notch and the Notch signalling which allowed the discovery of a core set of molecules involved pathway in Notch signalling and lead to the understanding of how they organize into a signalling pathway. The Notch genes encode members of a family of receptors that In mammals, there are four Notch genes and five genes mediate short-range signalling events. A prototypical Notch encoding ligands, three Delta-like and two Jagged (Fig. 1). In gene encodes a single transmembrane receptor composed in Drosophila, there is only one Notch-encoding gene, one Delta its extracellular region of a conserved array of up to 36 and one Jagged homologue (Serrate; Maine et al. 1995, epidermal growth factor (EGF)-like repeats, involved in Lissemore & Starmer 1999).
    [Show full text]
  • The Transcriptional Activator PAX3–FKHR
    Downloaded from genesdev.cshlp.org on September 28, 2021 - Published by Cold Spring Harbor Laboratory Press The transcriptional activator PAX3–FKHR rescues the defects of Pax3 mutant mice but induces a myogenic gain-of-function phenotype with ligand-independent activation of Met signaling in vivo Frédéric Relaix,1 Mariarosa Polimeni,2 Didier Rocancourt,1 Carola Ponzetto,3 Beat W. Schäfer,4 and Margaret Buckingham1,5 1CNRS URA 2375, Department of Developmental Biology, Pasteur Institute, 75724 Paris Cedex 15, France; 2Department of Experimental Medicine, Section of Anatomy, University of Pavia, 27100 Pavia, Italy; 3Department of Anatomy, Pharmacology and Forensic Medicine, University of Turin, 10126 Turin, Italy; 4Division of Clinical Chemistry and Biochemistry, Department of Pediatrics, University of Zurich, CH-8032 Zurich, Switzerland Pax3 is a key transcription factor implicated in development and human disease. To dissect the role of Pax3 in myogenesis and establish whether it is a repressor or activator, we generated loss- and gain-of-function alleles by targeting an nLacZ reporter and a sequence encoding the oncogenic fusion protein PAX3–FKHR into the Pax3 locus. Rescue of the Pax3 mutant phenotypes by PAX3–FKHR suggests that Pax3 acts as a transcriptional activator during embryogenesis. This is confirmed by a Pax reporter mouse. However, mice expressing PAX3–FKHR display developmental defects, including ectopic delamination and inappropriate migration of muscle precursor cells. These events result from overexpression of c-met, leading to constitutive activation of Met signaling, despite the absence of the ligand SF/HGF. Haploinsufficiency of c-met rescues this phenotype, confirming the direct genetic link with Pax3. The gain-of-function phenotype is also characterized by overactivation of MyoD.
    [Show full text]
  • The Proapoptotic Gene Interferon Regulatory Factor-1 Mediates the Antiproliferative Outcome of Paired Box 2 Gene and Tamoxifen
    Oncogene (2020) 39:6300–6312 https://doi.org/10.1038/s41388-020-01435-4 ARTICLE The proapoptotic gene interferon regulatory factor-1 mediates the antiproliferative outcome of paired box 2 gene and tamoxifen 1 1 1 2 3 3 Shixiong Wang ● Venkata S. Somisetty ● Baoyan Bai ● Igor Chernukhin ● Henri Niskanen ● Minna U. Kaikkonen ● 4,5 2 6,7 Meritxell Bellet ● Jason S. Carroll ● Antoni Hurtado Received: 13 November 2019 / Revised: 5 August 2020 / Accepted: 17 August 2020 / Published online: 25 August 2020 © The Author(s) 2020. This article is published with open access Abstract Tamoxifen is the most prescribed selective estrogen receptor (ER) modulator in patients with ER-positive breast cancers. Tamoxifen requires the transcription factor paired box 2 protein (PAX2) to repress the transcription of ERBB2/HER2. Now, we identified that PAX2 inhibits cell growth of ER+/HER2− tumor cells in a dose-dependent manner. Moreover, we have identified that cell growth inhibition can be achieved by expressing moderate levels of PAX2 in combination with tamoxifen treatment. Global run-on sequencing of cells overexpressing PAX2, when coupled with PAX2 ChIP-seq, identified common targets regulated by both PAX2 and tamoxifen. The data revealed that PAX2 can inhibit estrogen-induced gene transcription 1234567890();,: 1234567890();,: and this effect is enhanced by tamoxifen, suggesting that they converge on repression of the same targets. Moreover, PAX2 and tamoxifen have an additive effect and both induce coding genes and enhancer RNAs (eRNAs). PAX2–tamoxifen upregulated genes are also enriched with PAX2 eRNAs. The enrichment of eRNAs is associated with the highest expression of genes that positivity regulate apoptotic processes.
    [Show full text]
  • T-Box Genes in Limb Development and Disease
    Open Research Online The Open University’s repository of research publications and other research outputs T-box Genes in Limb Development and Disease Thesis How to cite: Rallis, Charalampos (2004). T-box Genes in Limb Development and Disease. PhD thesis The Open University. For guidance on citations see FAQs. c 2004 Charalampos Rallis Version: Version of Record Link(s) to article on publisher’s website: http://dx.doi.org/doi:10.21954/ou.ro.0000fa0b Copyright and Moral Rights for the articles on this site are retained by the individual authors and/or other copyright owners. For more information on Open Research Online’s data policy on reuse of materials please consult the policies page. oro.open.ac.uk T-box Genes in Limb Development and Disease Charalampos Rallis Thesis submitted for the degree of Doctor of Philosophy October 2004 Division of Developmental Biology National Institute for Medical Research Mill Hill London Open University ProQuest Number: C819643 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a com plete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. uest ProQuest C819643 Published by ProQuest LLO (2019). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States C ode Microform Edition © ProQuest LLO. ProQuest LLO. 789 East Eisenhower Parkway P.Q.
    [Show full text]
  • Epigenetics of Floral Homeotic Genes in Relation to Sexual Dimorphism in the 2 Dioecious Plant Mercurialis Annua
    bioRxiv preprint doi: https://doi.org/10.1101/481481; this version posted November 29, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 1 Epigenetics of floral homeotic genes in relation to sexual dimorphism in the 2 dioecious plant Mercurialis annua 3 4 Janardan Khadka1, Narendra Singh Yadav1†, Micha Guy1, Gideon Grafi1* and Avi Golan- 5 Goldhirsh1* 6 1French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein 7 Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben Gurion 8 84990, Israel. 9 †Present address: Department of Biological Sciences, University of Lethbridge, AB T1K 10 3M4, Canada. 11 * To whom correspondence should be addressed 12 13 14 Highlights 15 Sex determination in Mercurialis annua is not related to epigenetics of floral homeotic genes 16 but appears to be modulated by an unknown gender-specific regulator(s) that affects hormonal 17 homeostasis. 18 1 bioRxiv preprint doi: https://doi.org/10.1101/481481; this version posted November 29, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 19 Abstract 20 In plants, dioecy characterizes species carrying male and female flowers on separate plants 21 and occurs in about 6% of angiosperms. To date, the molecular mechanism(s) underlying 22 sexual dimorphism is essentially unknown. The ability of gender-reversal by hormone 23 application suggests that epigenetics might play an important role in sexual dimorphism.
    [Show full text]
  • Genomic Targeting of Epigenetic Probes Using a Chemically Tailored Cas9 System
    Genomic targeting of epigenetic probes using a chemically tailored Cas9 system Glen P. Liszczaka, Zachary Z. Browna, Samuel H. Kima, Rob C. Oslunda, Yael Davida, and Tom W. Muira,1 aDepartment of Chemistry, Princeton University, Princeton, NJ 08544 Edited by James A. Wells, University of California, San Francisco, CA, and approved December 13, 2016 (received for review September 20, 2016) Recent advances in the field of programmable DNA-binding proteins Here, we report a method that combines the versatility of have led to the development of facile methods for genomic pharmacologic manipulation with the specificity of a genetically localization of genetically encodable entities. Despite the extensive programmable DNA-binding protein. Our strategy uses a utility of these tools, locus-specific delivery of synthetic molecules chemically tailored dCas9 to display a pharmacologic agent at a remains limited by a lack of adequate technologies. Here we combine genetic locus of interest in live mammalian cells (Fig. 1). This is trans the flexibility of chemical synthesis with the specificity of a pro- accomplished using split intein-mediated protein -splicing grammable DNA-binding protein by using protein trans-splicing to (PTS) to site-specifically link a recombinant dCas9:guide RNA ligate synthetic elements to a nuclease-deficient Cas9 (dCas9) (gRNA) complex to the synthetic cargo of choice (22). Indeed, in vitro and subsequently deliver the dCas9 cargo to live cells. we show that the remarkable specificity, efficiency, and speed of PTS allow the direct generation of desired dCas9 conjugates The versatility of this technology is demonstrated by delivering within the cell culture media, thereby facilitating a streamlined dCas9 fusions that include either the small-molecule bromodomain “one-pot” approach for genomic targeting of the reaction product.
    [Show full text]
  • Geometry, Epistasis, and Developmental Patterning
    Geometry, epistasis, and developmental patterning Francis Corson and Eric Dean Siggia1 Center for Studies in Physics and Biology, The Rockefeller University, New York, NY 10021 This contribution is part of the special series of Inaugural Articles by members of the National Academy of Sciences elected in 2009. Contributed by Eric Dean Siggia, February 6, 2012 (sent for review November 28, 2011) Developmental signaling networks are composed of dozens of (5) shows that even differentiation can be reversed. Yet they have components whose interactions are very difficult to quantify in provided a useful guide to experiments. an embryo. Geometric reasoning enumerates a discrete hierarchy These concepts admit a natural geometric representation, of phenotypic models with a few composite variables whose para- which can be formalized in the language of dynamical systems, meters may be defined by in vivo data. Vulval development in also called the geometric theory of differential equations (Fig. 1). ’ the nematode Caenorhabditis elegans is a classic model for the in- When the molecular details are not accessible, a system s effec- tegration of two signaling pathways; induction by EGF and lateral tive behavior may be represented in terms of a small number of signaling through Notch. Existing data for the relative probabilities aggregate variables, and qualitatively different behaviors enum- of the three possible terminal cell types in diverse genetic back- erated according to the geometrical structure of trajectories or grounds as well as timed ablation of the inductive signal favor topology. The fates that are accessible to a cell are associated with attractors—the valleys in Waddington’s “epigenetic landscape” one geometric model and suffice to fit most of its parameters.
    [Show full text]
  • Pancreas-Specific Deletion of Mouse Gata4 and Gata6 Causes Pancreatic Agenesis
    Pancreas-specific deletion of mouse Gata4 and Gata6 causes pancreatic agenesis Shouhong Xuan, … , Raymond J. Macdonald, Lori Sussel J Clin Invest. 2012;122(10):3516-3528. https://doi.org/10.1172/JCI63352. Research Article Pancreatic agenesis is a human disorder caused by defects in pancreas development. To date, only a few genes have been linked to pancreatic agenesis in humans, with mutations in pancreatic and duodenal homeobox 1 (PDX1) and pancreas-specific transcription factor 1a (PTF1A) reported in only 5 families with described cases. Recently, mutations in GATA6 have been identified in a large percentage of human cases, and aG ATA4 mutant allele has been implicated in a single case. In the mouse, Gata4 and Gata6 are expressed in several endoderm-derived tissues, including the pancreas. To analyze the functions of GATA4 and/or GATA6 during mouse pancreatic development, we generated pancreas- specific deletions of Gata4 and Gata6. Surprisingly, loss of either Gata4 or Gata6 in the pancreas resulted in only mild pancreatic defects, which resolved postnatally. However, simultaneous deletion of both Gata4 and Gata6 in the pancreas caused severe pancreatic agenesis due to disruption of pancreatic progenitor cell proliferation, defects in branching morphogenesis, and a subsequent failure to induce the differentiation of progenitor cells expressing carboxypeptidase A1 (CPA1) and neurogenin 3 (NEUROG3). These studies address the conserved and nonconserved mechanisms underlying GATA4 and GATA6 function during pancreas development and provide a new mouse model to characterize the underlying developmental defects associated with pancreatic agenesis. Find the latest version: https://jci.me/63352/pdf Research article Related Commentary, page 3469 Pancreas-specific deletion of mouse Gata4 and Gata6 causes pancreatic agenesis Shouhong Xuan,1 Matthew J.
    [Show full text]
  • Sequential Organizing Activities of Engrailed, Hedgehog and Decapentaplegic in the Drosophila Wing
    Development 121, 2265-2278 (1995) 2265 Printed in Great Britain © The Company of Biologists Limited 1995 Sequential organizing activities of engrailed, hedgehog and decapentaplegic in the Drosophila wing Myriam Zecca1, Konrad Basler1 and Gary Struhl2 1Zoologisches Institut, Universität Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland 2Howard Hughes Medical Institute, Department of Genetics and Development, Columbia University College of Physicians and Surgeons, 701 West 168th Street, New York NY 10032 USA SUMMARY The Drosophila wing is formed by two cell populations, the strate that dpp can exert a long-range organizing influence anterior and posterior compartments, which are distin- on surrounding wing tissue, specifying anterior or posterior guished by the activity of the selector gene engrailed (en) in pattern depending on the compartmental provenance, and posterior cells. Here, we show that en governs growth and hence the state of en activity, of the responding cells. Thus, patterning in both compartments by controlling the dpp secreted by anterior cells along the compartment expression of the secreted proteins hedgehog (hh) and boundary has the capacity to organize the development of decapentaplegic (dpp) as well as the response of cells to both compartments. Finally, we report evidence suggesting these signaling molecules. First, we demonstrate that en that dpp may exert its organizing influence by acting as a activity programs wing cells to express hh whereas the gradient morphogen in contrast to hh which appears to act absence of en activity programs them to respond to hh by principally as a short range inducer of dpp. expressing dpp. As a consequence, posterior cells secrete hh and induce a stripe of neighboring anterior cells across the Key words: engrailed, decapentaplegic, hedgehog, Drosophila, compartment boundary to secrete dpp.
    [Show full text]
  • Genetic Dissection of Developmental Pathways*§ †
    Genetic dissection of developmental pathways*§ † Linda S. Huang , Department of Biology, University of Massachusetts-Boston, Boston, MA 02125 USA Paul W. Sternberg, Howard Hughes Medical Institute and Division of Biology, California Institute of Technology, Pasadena, CA 91125 USA Table of Contents 1. Introduction ............................................................................................................................1 2. Epistasis analysis ..................................................................................................................... 2 3. Epistasis analysis of switch regulation pathways ............................................................................ 3 3.1. Double mutant construction ............................................................................................. 3 3.2. Interpretation of epistasis ................................................................................................ 5 3.3. The importance of using null alleles .................................................................................. 6 3.4. Use of dominant mutations .............................................................................................. 7 3.5. Complex pathways ........................................................................................................ 7 3.6. Genetic redundancy ....................................................................................................... 9 3.7. Limits of epistasis ......................................................................................................
    [Show full text]