|Morphogenesis, Signaling, Modeling|
|Dynamics and Expression of plant Genomes|
|Adaptation of Plants to the Environment|
|Reproduction and Seeds|
|Plant cell wall, function and utilization|
by Mathilde Grelon
Raphaël Mercier, young Senior Scientist of his team « Meiosis mechanisms and apomixis », in the group « Meiosis and recombination », the Department « Dynamics and Expression of the Genome »,specialized very early on meiosis (the universal mechanism allowing to shuffle and distribute chromosomes during the formation of sexual cells). His interest in science began in ninth grade, and since 2003 he contributed in the group to the characterization of no less than sixty genes involved in meiosis, these results having heavy impact in the plant’s field. Axel Kahn, President of the « Comité d'éthique » Inra-Cirad-Ifremer, presented the INRA award "Scientific challenge ( « Défi scientifique 2016 ») during the 11th ceremony the 13th december 2016.
Raphaël Mercier explains us: «
The genes involved in meiosis are remarkably well conserved among organisms
as different as yeasts, plants, mice, and humans. Therefore, identifying
such genes in the plant model Arabidopsis thaliana should help
us identify their homologs in other species, but working with Arabidopsis
is much easier. »
The stimulating context of a cohesive
research group of around thirty people with the unique facilities of IJPB
to grow and study plants (green houses, culture chambers and platforms
of the Plant Observatory) are in favor of a top-level research. Raphaël’s
scientific works has been awarded of several scientific prices, the first
one as earlier as for is PhD thesis. His research results on apomixis
(see IJPB news «A new way to clone plants») were one of the
10 discoveries of the year 2011 of the journal « La Recherche ».
A « Starting Grant » of the European Council (ERC) with a
financial support of 5 years (2012-16) allowed the development of is work
and his team.
In plant, the senescence of leaves, petals
and pods is characterized by a large set of macroscopic and microscopic
phenotypes, which result from highly controlled sequential molecular events.
Essential to nutrient management, nitrogen remobilisation and more globally
to the adaptation of plants to their environment, senescence is a trait
of interest in agriculture.
European students research training
In the frame of the ITN (Initial Training Network) project Croplife, 9 students were hosted for two weeks by the research group "Signalisation and nutritional recycling" of the scientific pole "Adaptation of Plants to the Environment" at INRA in Versailles from the 4th to the 15th of June 2012. This programme involves 9 research laboratories. During these 3 years, a large choice of training courses, summer schools, meeting and workshops is provided. The oppotunity to exchange experiences, ideas and friendship. In the course of these 2 weeks in Versailles, students had benefit of the laboratory and teaching structures of IJPB, particularly the microscopy platform (PCIV) and plant chemistry platform (PFCV).
Programme and list of the students
TOR (Target of Rapamycin, an antibiotic) is a conserved protein kinase present in animals, yeast and plants which controls cell growth and a wide range of metabolic processes. The plant TOR field is still in its infancy but is now growing rapidly thanks to recent and important contributions. Therefore we thought that it was time to gather the teams involved in this field of research for informal exchanges and discussions in this year marking the 20th anniversary of the discovery of TOR. We hope that this meeting will help in building a research community around this exciting and central regulatory pathway.
Chromatin is the structure organizing the genetic information in the nucleus of higher organisms. The dynamics of this structure allows a fine-tuning of gene expression and control of genome integrity. Chromatin is therefore essential for various cellular and developmental processes and participates to responses to environmental cues.
Fifty five participants from 12 European countries joined the 2011 EWPC edition. This year, studies on other plant models such as rice and moss enriched the discussion besides Arabidopsis thaliana. A new research topic initiated from a collaboration established during the first EWPC, which was held in Zürich in 2009, was presented. The next meeting will be held in 2013, in Madrid.
During the EWPC2011, the participants discovered the King’s Vegetable Garden in Versailles and tasted delicious fruit juices. Many thanks to M. Pierre-Henri Duée, the President of the INRA Versailles-Grignon center, who made this visit possible and to all who did contribute to the success of the workshop.
Program (.pdf file)
For more information, please contact and visit our website Second European Workshop on Plant Chromatin 2011
First European Brachypodium Workshop
October, 19th 20th & 21th, 2011
Brachypodium is now widely recognized as
a new model system in numerous American, Asian and European laboratories
interested for instance in cereal genomics, bioenergy and evo-devo. Despite
the active contribution of these laboratories to the development of genomics
tools, some scientific advances remain poorly visible at least in Europe.
The goal of the first European Brachypodium workshop is to bring together
the Brachypodium community, to communicate on research, results, problems
and bottlenecks encountered with this new model plant. The meeting would
cover a large panel of plant biology, genetic variability of wild populations,
biotic and abiotic stresses and recently developed genomic tools. The
workshop will be open but limited to 150 people. Preliminary program and
registration instructions will be communicated later.
The Institut Jean-Pierre Bourgin partner
of the new Labex SPS :
The current research activities of the Labex concern the essential genetic, molecular and cellular mechanisms that control plant physiology and development, as well as their interactions with fluctuating biotic or abiotic environments. These studies extend from the cell to the entire plant, and use the concepts and tools of biochemistry, biophysics, imaging, molecular biology, genetics, cell biology, modelling and bioinformatics. The four laboratories of the SPS Labex (IBP, IJPB, ISV, URGV) include about 400 permanent staff members and 150 PhD students and post-doctoral researchers. The members of the SPS Labex provide around 7500 hours of teaching and training per year. SPS laboratories host several internationally renowned leaders and talented young investigators.
The strategy described above will be
implemented by different types of initiatives and cross-cutting actions.
This will include a few strategic and integrative flagship projects headed
by internationally recognized leaders. These projects will be evaluated
after 4 years by an international scientific advisory board. A grant program
will be launched on a yearly basis, in the areas of four relevant thematic
priorities, to support the valorisation of results, the emergence of new
topics and the starting phase of new researchers/faculty. The four thematic
priorities relevant to the socio-economic and scientific contexts will
be: 1) the sustainable intensification of plant productivity in a fluctuating
environment; 2) plants as factories: improving plant quality for food,
feed, health, environment and industry; 3) plants to understand fundamental
biological mechanisms; and 4) developing new resources and biotechnologies
for research, innovation, and technology transfer.
Contact : coordinator Loïc Lepiniec
Avril 6th 2011
The most interesting plants, that combine a large number of traits, often have a complex genetic composition. Because sexual reproduction mixes genetic information at each generation, their progeny do not retain targeted traits. However, the progeny of these same plants obtained by apomixis could conserve these traits and be reproduced and distributed endlessly. Apomixis has not yet been introduced in species of major agricultural interest. Apomixis – the cloning of plants through seeds – results from changes to two steps in the process of sexual reproduction: the formation of gametes which carry all the genetic information of the mother plant instead of half (2n chromosomes rather than n), and the initiation of embryogenesis without pollination (i.e. without the genetic information of the father plant).
The first component of apomixis can be
introduced in Arabidopsis using MiMe
or dyad mutants, previously obtained by the teams of Raphaël
Mercier (INRA, France) and Imran Siddiqi (CSIR, India). The 2n-chromosome
gametes produced by these mutants normally play a role in sexual reproduction.
The progeny thus obtained by fertilisation carry double the number of
chromosomes (4n instead of 2n) and are therefore different to the mother
plant which has 2n chromosomes.
INRA Versailles-Grignon and CSIR researchers combined both components of apomixis (MiMe or dyad on one hand, GEM on the other). This work demonstrated that clonal seeds wholly identical to the mother or father plant can effectively be obtained by crossing MiMe and dyad plants to the GEM line.
These results demonstrate that clonal reproduction can be introduced in a sexual plant by modifying just a few genes, and constitute a proof of principle for the development of apomixis in cultivated plants.
(1) GEM stands for “Genome Elimination induced by a Mix of CENH3 variants”
© INRA 2010