Press release-The secret of plant growth

Unlike animals, plants have cells that are all surrounded by a rigid wall. It protects them but encloses them in a rigid skeleton. So how can they grow despite this wall?

In order to understand how a plant grows, it is essential to unravel the process of assembly and elongation of the plant cell wall. A consortium of INRAE researchers and their Swiss and Belgian collaborators have demonstrated how the interaction between pectins and proteins controls wall growth.

The pollen tube, a unicellular organ of the model plant Arabidopsis, shows growth oriented at its tip. Uncharged pectins accumulate there and their enzymatic modification generates the appearance of negative charges. They are then recognised by a complex formed by a peptide (RALF4) and its receptor (LRX8). This interaction causes the pectins to condense, creating a cross-linked pattern that confers strength and extensibility to the wall.

These results obtained as part of the ANR Homeowall project are fundamental to our understanding of plant growth mechanisms. They are also extremely important for modelling and predicting the effects of environmental changes on the growth of cultivated plants.