The activities of the MSM department "morphogenesis, signaling, modeling" are dedicated to the study of the mechanisms of plant morphogenesis. Our studies are focused primarily on the cellular level (control of cell division, cell polarity ...) but also extend to the whole plant (eg signaling between organs). We are interested in the issues of totipotency and cell differentiation in the plant but also in vitro. We use modeling approaches to better understand these complex phenomena.
The teams from the MSM department not only work on biological models such as Arabidopsis thaliana, Brachypodium or the moss Physcomitrella patens but also on species of agronomic interest such as pea or cotton. We mainly use classical approaches of genetics and functional genomics complemented by methods of biochemistry and chemistry. We exploit many imaging techniques for which we develop novel quantitative approaches. The purpose of our work is a better understanding of plant development in order to propose innovative strategies to improve plant resources and their uses. This happens, for example by modifying plant architecture, and further upstream, by improving processing techniques and regeneration.
Cell to Cell adhesion and Communication »
studies the network of polysaccharides, plant cell wall components
linking the cells together, to better understand mechanisms
responsible for cohesion during the cellular dynamics all
along the growth and the development of the plant. The group
uses the model plants Arabidopsis thaliana and Brachypodium
distachychion concerning respectively dicotyledonous and grasses.
More recently, rice, a crop plant, is also studied.
team « Biology
of the Cell and Regeneration »
is focused on control of regeneration technics by organogenesis
or somatic embryogenesis and genes transfer to in vitro
grown plant cells. Objectives concern fundamental uses (transient
activities, "knock-out"...) or more focused studies
(resistance to abiotic stresses, biomass use…). Model
plants Arabidopsis thaliana and Brachypodium distachyon
and also agronomical important crops sorghum and cotton are
the studied species. The group is involved in a project aimed
to characterize cell regenerating transcriptome profiles (organogenesis
in Arabidopsis thaliana and somatic embryogenesis
team « Spatial
control of cell division » In higher
plants, the cytoskeleton steadily undergoes structural reorganizations
which accompany and/or determine every stage in cell division,
elongation and differentiation. Our aim is to characterize
cellular activities and regulation networks involved in the
organization of microtubule arrays during the cell cycle in
land plants. Our studies are focused on entry into mitosis
and premitotic determination of the division plane in plant
cells. We try to clarify the role of the preprophase band,
a specific feature of plant cells, and more generally to explore
the links between the microtubule cytoskeleton and the cell
cycle machinery. Recent results of the group have revealed
a large regulatory complex (TTP) composed of several protein
partners. The recruitment of the TTP complex to the cytoskeleton,
and its activity at the G2/M transition are necessary for
division plane determination and PPB formation in Arabidopsis
and moss. This complex also plays a pivotal role in the organization
of the interphase array during diffuse growth.
team « Branching control in plants »
aims to have a better understanding of the genetic, molecular
and physiological factors that control axillary buds outgrowth
or dormancy. In particular, we focus on the biosynthesis and
the signaling pathways of a novel class of phytohormones,
the strigolactones, which inhibit branching. Our work is based
on a large collection of pea mutants specifically affected
in stem branching. The same genes are studied in the moss
Physcomitrella patens, to better understand the evolution
of strigolactone function in land plants.
team « Cell
differentiation and polarity »
studies cellular mechanisms of development associated to the
acquisition of cell identity thought two models: tumor mutants
and phloem ontogenesis. The group is focused on the role of
fatty acids on cell differentiation and polarity, particularly
on biosynthesis, compartmentalization and the role of long
chain fatty acids in general and more precisely sphingolipids.
Role of palmitoylation is also studied.
team « Transcription factors and plant architecture »
focuses on the mechanisms controlling the morphogenesis of
the aerial part of plants and on their evolution. For this,
we study the function of two families of transcription factors
(homeodomain proteins of the TALE family proteins and NAM
/ CUC proteins regulated by the microRNA miR164) in the development
of meristems, leaves and flowers in Arabidopsis and other
team « Modeling and Digitial Imaging »
develops methods, algorithms and tools for processing, analyzing
and modeling data generated, primarily, by biological imaging
techniques. We aim, on the one hand, at unraveling principles
of spatial organization and, on the other hand, at understanding
the factors and mechanisms that subtend these principles.
Our activity is thus at the intersection of image processing
and analysis, spatial statistics, and modeling.
team « Chromatin dynamics and signalling »
aims to better understand developmental and environmental
signalling mechanisms, and their interplay with chromatin
dynamics and nuclear architecture, to approach the delicate
equilibrium between signalling pathways. To do so, we exploit
different biological contexts.