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Accueil du site > Equipes de recherche > Protéines pariétales et Développement > Thèmes de recherche > Fonctional study of plant cell wall proteomes : Spatio-temporal and ultrastructural approaches

Fonctional study of plant cell wall proteomes : Spatio-temporal and ultrastructural approaches

Contacts  : mail to Vincent BURLAT, mail to Valérie PACQUIT

Traditional models of the plant cell wall illustrate the interconnections of the different cell wall polymers (cellulose, hemicelluloses, pectins, proteins...). The dynamic nature of plant cell wall is now widely accepted. As a consequence, even if the plant cell wall is still sometimes considered as a single entity, more and more studies take into account the specific composition of plant cell walls within different species, different cell types, different sub-layers or different developmental stages.

It is within this context that we focus on the functional study of plant cell wall proteomes with special attention to the plant cell wall proteome of Arabidopsis thaliana etiolated hypocotyls established by our team (Irshad et al. 2008, Zhang et al. 2010). The originality of our approach is to fully integrate the parameter of spatio-temporal heterogeneity or in other words to keep in mind that there is not a single wall, but rather various plant cell walls whose composition varies in different cell types during development, both in terms of proteins and cell wall polymers.

From a methodological perspective, this project aims to establish systematic relationships between three types of parameters :

(1) the classification of the plant cell wall proteome in 9 putative functional groups [already established by our team on the basis of in silico analysis (Jamet et al. 2008)
(2) the spatio-temporal expression patterns of genes encoding studied cell wall proteins (a systematic study by in situ RNA hybridization has been undertaken)
(3) the cell-specific composition of plant cell walls during development (already known or to be established with immunocytochemistry using antibodies directed against different cell wall polymers).

The candidates for whom this type of inter-relationships may be appropriately established are selected for a more thorough functional study. As an example, the first selected candidates are genes encoding lipid metabolism proteins (parameter 1), preferentially expressed in the epidermis (parameter 2) and that could be involved in the assembly of the lipidic cuticle (parameter 3). The functional study particularly aims to clarify the subcellular localization of the corresponding proteins, the cuticle micro-phenotypes in deregulated plant lines (overexpression, knockout mutants, RNAi), in vitro activities of recombinant proteins...