Download Gregor Mendel Institute of Molecular Plant Biology, GMI

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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-
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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.
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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
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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.