The skin of plants

The cuticle covers the surface of all plants and performs vital biological functions for the plant (resistance to dehydration, adaptation to climatic and biological stresses). These properties are determined by the particular structuring of the cuticle, a natural composite comprising lipids (cutins) and walls (polysaccharides). However, this has not yet been clarified. In particular, the walls embedded in the cutin lipid polymer were not readily available for investigation and their nature was unknown.

Using tomato fruit as a model, the combination of suitable pre-treatment methods (chemical and enzymatic) coupled with several complementary investigation methods (spectral, biochemical, immunocytochemistry, mapping) made it possible for the first time to establish the fine structure of the walls embedded in the cutin polymer (CEP). The characteristics of these PECs (composition, hydrophobicity, crystallinity) are very different from those of the uncutinized plant walls, which assumes a particular role in the functions of the cuticle. In addition, the research team showed that a change in the degree of cutin polymerization leads to specific changes in FFS, which shows a lipid/wall dialog in the cuticle assembly.

These results open up new avenues for knowledge of cuticle construction in the plant, or for the construction of new bio-inspired materials.

Partners: This study was carried out by the unité BIA (in Nantes) in collaboration with the Biologie Pathologie du Fruit unit (Bordeaux) and the SMIS line of the SOLEIL synchrotron.

Funding: this study was carried out within the framework of the thesis INRAE-Région Pays de la Loire de Glenn Philippe.