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Gregor Mendel Institute of Molecular Plant Biology, GMI

Head: Dieter Schweizer

Aims and Functions Research at the GMI is curiosity driven and currently The Institute of Molecular Plant Biology focuses on the genetic and epigenetic plasticity of the (GMI GmbH) was founded by the Austrian Academy of plant genome in the contexts of gene regulation, chro- Sciences in 2000 to promote research excellence within mosome biology and development. We share a common the field of plant . The GMI is the first interest in with the IMP and IMBA. GMI and only international centre for basic plant research in scientists also study the nature and crosstalk of plant sig- . Since January 2006, it has been located at the nal transduction pathways in response to intrinsic and Biocenter Campus – which encompasses both environmental stimuli at both the genetic and epigenetic independent and academic research institutes and com- levels. is used as the primary model panies. One of the GMI’s great strengths lies in its prox- organism. Research groups are evaluated annually by an imity to institutions undertaking biomedical research. international Scientific Advisory Board. Research at the We share a building, the Austrian Academy of Sciences GMI is supported primarily by the Austrian Academy of Life Sciences Center Vienna, with the Institute of Mo- Sciences, complemented by grants obtained from various lecular Biotechnology (IMBA) and are internally con- funding agencies. In the years 2004/2005, GMI group nected to the adjacent Research Institute of Molecular leaders received external grants from the Austrian Sci- Pathology (IMP) of Boehringer Ingelheim. Neighbour- ence Fund (FWF), the European Commission and the ing research units include the Max F. Perutz Laboratories European Science Foundation. In addition, in 2005, four (MFPL) of the Medical and the research groups from the GMI (Werner Aufsatz, Claudia University of Vienna and some biomedical start-up com- Jonak, Ortrun Mittelsten Scheid, Karel Riha) were panies. Such an arrangement is very rare for plant research awarded a highly competitive GEN-AU grant, funded by institutes around the world and promotes crosstalk, inter- the Austrian Federal Ministry for Education, Science and disciplinary collaboration and, hence, innovative research Culture, for the project ‘Lasting effects of abiotic stress in the fields of both plant and biomedical sciences. in plant genomes and their potential for breeding strate- Research at the GMI is organised into three levels of gies’ (start date: April 2006). independent research units: (1) major research groups headed by a Senior Scientist, (2) smaller research groups Results for 2004–2005 headed by a Junior Principal Investigator (JPI) and (3) In 2004, the GMI (until then consisting only of the Di- GMI Young Investigator Group (YIG) positions intro- rector’s Group) welcomed two new major research duced in 2005. Senior Scientists have long-term con- groups: Marjori and Antonius Matzke (Academy Insti- tracts, while Junior Principal Investigators and Young tute of Molecular Biology, Salzburg, Austria), who Investigators have contracts of eight and five years, re- moved into a temporary laboratory at the Pharmacy spectively. This guarantees both continuity as well as Center of the University of Vienna; and Ortrun Mit- change and renewal. GMI’s research activities will be telsten Scheid (Friedrich Miescher Institute, Basel, Swit- supported by a platform consisting of the GMI’s own zerland), whose group was kindly hosted by Marie-Theres service units as well as joint IMP-IMBA services. GMI Hauser and Josef Glössl in the Center of Applied Genet- is a non-profit making basic research institution. All dis- ics of the University of Natural Resources and Applied coveries are screened for patentability before publication Life Sciences (BOKU, Vienna). to secure a partial return of the Austrian Academy of In July 2005, Werner Aufsatz (Matzke Group) and Karel Sciences’ significant start-up investment. Riha (Director’s Group) were promoted to become the Gregor Mendel Institute of Molecular Plant Biology, GMI 15 first independent Young Investigators. The third Young ised histone modifications is the acetylation of conserved Investigator to be appointed was Claudia Jonak from the lysine residues in histone-tails, a process that is dynami- University of Vienna. In summer 2005, the GMI joined cally regulated by the activity of histone acetyltransferas- the prestigious International PhD Pro- es (HATs) and histone deacetylases (HDACs). Silenced, gram in Molecular Life Sciences, and by the end of the inactive gene regions are usually associated with hy- year, the first PhD students of this program took up their poacetylated histones. thesis work at the GMI. The first SAB Meeting of the The research of Werner Aufsatz deals with HDACs in GMI was held in October 2005. The late autumn of RNA silencing and stress adaptation. His present activi- 2005 was marked by the start of the long-awaited reloca- ties focus on the function of Arabidopsis Rpd3-type tion of the six GMI research groups from five different HDACs. Using genetic, biochemical and molecular ap- temporary locations in Vienna into purpose-built premi- proaches, the Aufsatz Group studies the role of HDACs ses in the Austrian Academy of Sciences Life Sciences Cen- in homology-dependent gene silencing initiated by dou- ter Vienna at the Vienna Biocenter Campus. ble-stranded RNA and in regulatory processes resulting in stress adaptation. A deeper understanding of the un- Epigenetics derlying molecular mechanism is gained by the study of While the DNA is the molecule that stores genetic in- Arabidopsis plants that carry a mutation in the HDA6 formation and, hence, confers the material basis of Men- gene (Fig. 1). delian , it is the variations in chromatin structure Epigenetic regulation affects numerous processes in plants and composition that modulates its use, in other words and other eukaryotic organisms. In 2004/2005, research the expression of the genome. Marks on the chromatin, in the Matzke Group focused on the molecular machin- in addition to the DNA sequence, collectively contribute ery of RNA-mediated transcriptional gene silencing, en- to determining the cellular phenotype and can be so- dogenous pararetroviruses in the context of genome evo- matically inherited in subsequent cell divisions, and pos- lution, and interphase organisation in Ara- sibly also in subsequent generations. This phenomenon bidopsis. In July 2005, the Matzke Group published their is called ‘epigenetics’. Multiple combinatorial modifica- results on the discovery of atypical RNA polymerase tions of histone proteins, around which DNA is wound, subunits required for RNA-directed DNA methylation determine chromatin state; these modifications are in the prestigious journal Nature Genetics. A further 13 known as the ‘histone-code’. One of the best character- articles were published in peer-reviewed journals.

Fig.1: A: The arrow in the upper part marks the 190 bp long NPTII RNA which is detected in this experiment. As a normalisation control, transcript levels of the eIF-4A gene are shown in the lower part. B: In hda6 mutants (rts1), DNA methylation within the reporter promoter is significantly reduced compared to wild-type plants, especially at cytosines within a CG context. 16 Gregor Mendel Institute of Molecular Plant Biology, GMI

Fig. 2: Plants respond to environmental stress. Plants are perma- nently exposed to a multitude of external stimuli, which plant cells have to trans- form into physiologi- cally-intelligible sig- nals. Extracellular stimuli are perceived and internalised by various cellular recep- tors and are subse- quently transduced by signalling cascades to induce appropriate cellular responses that ultimately lead to physiological and developmental modifi- cations.

Another facet is epigenetic phenomena in relation to Chromosome Biology genome mutations and polyploidy. Polyploidisation, the The Riha Group uses Arabidopsis to investigate the mo- multiplication of whole chromosome complements, is lecular mechanisms involved in various aspects of chro- associated with epigenetic changes; that is, heritable al- mosome metabolism. The group’s two main interests are terations in gene expression levels. This is the major re- the function of DNA repair proteins in telomere main- search focus of the Mittelsten Scheid Group, which is tenance, especially the Ku70/80 heterodimer, and pro- pioneering studies on the molecular mechanism underly- gression through meiosis. Meiosis in plants is the special- ing polyploidy-associated gene silencing in the model ised form of cell division that occurs in the diploid spo- plant Arabidopsis. The Mittelsten Scheid Group is part rophyte, resulting in the formation of haploid spores, of the joint GEN-AU project ‘Lasting effects of abiotic which then develop into the gametophyte. The Direc- stress in plant genomes and their potential for breeding tor’s Group studies the early prophase of meiosis I, espe- strategies’. cially the role of DNA repair proteins in conjunction with homologous recombination. Publication highlights Signal Transduction Pathways and Stress Response include a research paper in the prestigious journal The Plants are exposed to changing intrinsic and environmen- Plant Cell in August 2004 about the role of Mre11 in tal stimuli that modulate their growth and development. genome stability in Arabidopsis. Environmental cues are mediated by integrated signal transduction systems to coordinate physiological re- Preview for 2006–2007 sponses (Fig. 2). The Jonak Group studies the connectiv- New Junior Principal Investigator Positions. In May 2005, ity between stress signal transduction and physiological the GMI announced a call in Nature for outstanding responses. The ongoing research work of the group fo- candidates from all areas of molecular and cellular plant cuses on a group of protein kinases, the plant glycogen biology to apply for two new Junior Principal Investiga- synthase kinase 3/shaggy-like kinases (GSK). Functional tor Positions scheduled to start in 2006. A search com- analyses of the Jonak Group revealed a new important mittee was established which prepared a short-list of six role of MsK4 at the interface between signal transduc- candidates, from a total of 76 applications, to be invited tion and metabolism. A new connection was discovered for interview. As a result of the final round, which in- between MsK4 activity and osmotic stress. This research cluded oral presentations, hearings and personal inter- will be part of the joint GEN-AU project ‘Lasting effects views, Dr. Thomas Greb (John Innes Centre, Norwich, of abiotic stress in plant genomes and their potential for UK) and Dr. Hisashi Tamaru (National Institute of Ge- breeding strategies’. netics, Japan) were invited for further negotiations. Both Gregor Mendel Institute of Molecular Plant Biology, GMI 17 candidates accepted the GMI’s offer to lead a Junior mid-term, the GMI plans to strengthen its research in Group for the duration of five years (with an option for cell biology and development by the establishment of an a three-year extension provided they receive a positive additional senior group in this area. Further investment evaluation from the Scientific Advisory Board after 4 by the Austrian Academy of Sciences will allow the insti- years). The two new Junior PrincipaI Investigator groups tute to continue to grow to reach the planned critical size will start early in 2006. as stipulated in the GMI’s strategic concept paper ap- What does the future hold? In the short-term, our integra- proved by the Austrian Academy of Sciences in Decem- tion at the Vienna Biocenter Campus is a priority. In the ber 2001.