Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Transgenerational epigenetic inheritance wikipedia , lookup
Epigenetics of neurodegenerative diseases wikipedia , lookup
Epigenomics wikipedia , lookup
Genetic engineering wikipedia , lookup
Microevolution wikipedia , lookup
Behavioral epigenetics wikipedia , lookup
Artificial gene synthesis wikipedia , lookup
14 Gregor Mendel Institute of Molecular Plant Biology, GMI Head: Dieter Schweizer Aims and Functions The Gregor Mendel Institute of Molecular Plant Biology (GMI GmbH) was founded by the Austrian Academy of Sciences in 2000 to promote research excellence within the field of plant molecular biology. The GMI is the first and only international centre for basic plant research in Austria. Since January 2006, it has been located at the Vienna Biocenter Campus – which encompasses both independent and academic research institutes and companies. One of the GMI’s great strengths lies in its proximity to institutions undertaking biomedical research. We share a building, the Austrian Academy of Sciences Life Sciences Center Vienna, with the Institute of Molecular Biotechnology (IMBA) and are internally connected to the adjacent Research Institute of Molecular Pathology (IMP) of Boehringer Ingelheim. Neighbouring research units include the Max F. Perutz Laboratories (MFPL) of the Medical University of Vienna and the University of Vienna and some biomedical start-up companies. Such an arrangement is very rare for plant research institutes around the world and promotes crosstalk, interdisciplinary collaboration and, hence, innovative research in the fields of both plant and biomedical sciences. Research at the GMI is organised into three levels of independent research units: (1) major research groups headed by a Senior Scientist, (2) smaller research groups headed by a Junior Principal Investigator ( JPI) and (3) GMI Young Investigator Group (YIG) positions introduced in 2005. Senior Scientists have long-term contracts, while Junior Principal Investigators and Young Investigators have contracts of eight and five years, respectively. This guarantees both continuity as well as change and renewal. GMI’s research activities will be supported by a platform consisting of the GMI’s own service units as well as joint IMP-IMBA services. GMI is a non-profit making basic research institution. All discoveries are screened for patentability before publication to secure a partial return of the Austrian Academy of Sciences’ significant start-up investment. Research at the GMI is curiosity driven and currently focuses on the genetic and epigenetic plasticity of the plant genome in the contexts of gene regulation, chromosome biology and development. We share a common interest in epigenetics with the IMP and IMBA. GMI scientists also study the nature and crosstalk of plant signal transduction pathways in response to intrinsic and environmental stimuli at both the genetic and epigenetic levels. Arabidopsis thaliana is used as the primary model organism. Research groups are evaluated annually by an international Scientific Advisory Board. Research at the GMI is supported primarily by the Austrian Academy of Sciences, complemented by grants obtained from various funding agencies. In the years 2004/2005, GMI group leaders received external grants from the Austrian Science Fund (FWF), the European Commission and the European Science Foundation. In addition, in 2005, four research groups from the GMI (Werner Aufsatz, Claudia Jonak, Ortrun Mittelsten Scheid, Karel Riha) were awarded a highly competitive GEN-AU grant, funded by the Austrian Federal Ministry for Education, Science and Culture, for the project ‘Lasting effects of abiotic stress in plant genomes and their potential for breeding strategies’ (start date: April 2006). Results for 2004–2005 In 2004, the GMI (until then consisting only of the Director’s Group) welcomed two new major research groups: Marjori and Antonius Matzke (Academy Institute of Molecular Biology, Salzburg, Austria), who moved into a temporary laboratory at the Pharmacy Center of the University of Vienna; and Ortrun Mittelsten Scheid (Friedrich Miescher Institute, Basel, Switzerland), whose group was kindly hosted by Marie-Theres Hauser and Josef Glössl in the Center of Applied Genetics of the University of Natural Resources and Applied Life Sciences (BOKU, Vienna). In July 2005, Werner Aufsatz (Matzke Group) and Karel Riha (Director’s Group) were promoted to become the Gregor Mendel Institute of Molecular Plant Biology, GMI first independent Young Investigators. The third Young Investigator to be appointed was Claudia Jonak from the University of Vienna. In summer 2005, the GMI joined the prestigious Vienna Biocenter International PhD Program in Molecular Life Sciences, and by the end of the year, the first PhD students of this program took up their thesis work at the GMI. The first SAB Meeting of the GMI was held in October 2005. The late autumn of 2005 was marked by the start of the long-awaited relocation of the six GMI research groups from five different temporary locations in Vienna into purpose-built premises in the Austrian Academy of Sciences Life Sciences Center Vienna at the Vienna Biocenter Campus. Epigenetics While the DNA is the molecule that stores genetic information and, hence, confers the material basis of Mendelian genetics, it is the variations in chromatin structure and composition that modulates its use, in other words the expression of the genome. Marks on the chromatin, in addition to the DNA sequence, collectively contribute to determining the cellular phenotype and can be somatically inherited in subsequent cell divisions, and possibly also in subsequent generations. This phenomenon is called ‘epigenetics’. Multiple combinatorial modifications of histone proteins, around which DNA is wound, determine chromatin state; these modifications are known as the ‘histone-code’. One of the best character- 15 ised histone modifications is the acetylation of conserved lysine residues in histone-tails, a process that is dynamically regulated by the activity of histone acetyltransferases (HATs) and histone deacetylases (HDACs). Silenced, inactive gene regions are usually associated with hypoacetylated histones. The research of Werner Aufsatz deals with HDACs in RNA silencing and stress adaptation. His present activities focus on the function of Arabidopsis Rpd3-type HDACs. Using genetic, biochemical and molecular approaches, the Aufsatz Group studies the role of HDACs in homology-dependent gene silencing initiated by double-stranded RNA and in regulatory processes resulting in stress adaptation. A deeper understanding of the underlying molecular mechanism is gained by the study of Arabidopsis plants that carry a mutation in the HDA6 gene (Fig. 1). Epigenetic regulation affects numerous processes in plants and other eukaryotic organisms. In 2004/2005, research in the Matzke Group focused on the molecular machinery of RNA-mediated transcriptional gene silencing, endogenous pararetroviruses in the context of genome evolution, and interphase chromosome organisation in Arabidopsis. In July 2005, the Matzke Group published their results on the discovery of atypical RNA polymerase subunits required for RNA-directed DNA methylation in the prestigious journal Nature Genetics. A further 13 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 permanently exposed to a multitude of external stimuli, which plant cells have to transform into physiologically-intelligible signals. Extracellular stimuli are perceived and internalised by various cellular receptors and are subsequently transduced by signalling cascades to induce appropriate cellular responses that ultimately lead to physiological and developmental modifications. Another facet is epigenetic phenomena in relation to genome mutations and polyploidy. Polyploidisation, the multiplication of whole chromosome complements, is associated with epigenetic changes; that is, heritable alterations in gene expression levels. This is the major research focus of the Mittelsten Scheid Group, which is pioneering studies on the molecular mechanism underlying polyploidy-associated gene silencing in the model plant Arabidopsis. The Mittelsten Scheid Group is part of the joint GEN-AU project ‘Lasting effects of abiotic stress in plant genomes and their potential for breeding strategies’. Signal Transduction Pathways and Stress Response Plants are exposed to changing intrinsic and environmental stimuli that modulate their growth and development. Environmental cues are mediated by integrated signal transduction systems to coordinate physiological responses (Fig. 2). The Jonak Group studies the connectivity between stress signal transduction and physiological responses. The ongoing research work of the group focuses on a group of protein kinases, the plant glycogen synthase kinase 3/shaggy-like kinases (GSK). Functional analyses of the Jonak Group revealed a new important role of MsK4 at the interface between signal transduction and metabolism. A new connection was discovered between MsK4 activity and osmotic stress. This research will be part of the joint GEN-AU project ‘Lasting effects of abiotic stress in plant genomes and their potential for breeding strategies’. Chromosome Biology The Riha Group uses Arabidopsis to investigate the molecular mechanisms involved in various aspects of chromosome metabolism. The group’s two main interests are the function of DNA repair proteins in telomere maintenance, especially the Ku70/80 heterodimer, and progression through meiosis. Meiosis in plants is the specialised form of cell division that occurs in the diploid sporophyte, resulting in the formation of haploid spores, which then develop into the gametophyte. The Director’s Group studies the early prophase of meiosis I, especially the role of DNA repair proteins in conjunction with homologous recombination. Publication highlights include a research paper in the prestigious journal The Plant Cell in August 2004 about the role of Mre11 in genome stability in Arabidopsis. Preview for 2006–2007 New Junior Principal Investigator Positions. In May 2005, the GMI announced a call in Nature for outstanding candidates from all areas of molecular and cellular plant biology to apply for two new Junior Principal Investigator Positions scheduled to start in 2006. A search committee was established which prepared a short-list of six candidates, from a total of 76 applications, to be invited for interview. As a result of the final round, which included oral presentations, hearings and personal interviews, Dr. Thomas Greb ( John Innes Centre, Norwich, UK) and Dr. Hisashi Tamaru (National Institute of Genetics, Japan) were invited for further negotiations. Both Gregor Mendel Institute of Molecular Plant Biology, GMI candidates accepted the GMI’s offer to lead a Junior Group for the duration of five years (with an option for a three-year extension provided they receive a positive evaluation from the Scientific Advisory Board after 4 years). The two new Junior PrincipaI Investigator groups will start early in 2006. What does the future hold? In the short-term, our integration at the Vienna Biocenter Campus is a priority. In the 17 mid-term, the GMI plans to strengthen its research in cell biology and development by the establishment of an additional senior group in this area. Further investment by the Austrian Academy of Sciences will allow the institute to continue to grow to reach the planned critical size as stipulated in the GMI’s strategic concept paper approved by the Austrian Academy of Sciences in December 2001.