Know more

A fundamental question in biology is how multicellular organisms robustly produce organ shapes. The underlying process of morphogenesis involves the integration of biochemical, genetic, and mechanical factors across multiple spatio-temporal scales. In plants, morphogenesis is dominated by the rigid cell wall, which fixes cells in their position. Adjacent cells must therefore coordinate their growth patterns, which are in turn controlled by the mechanical properties of the cell wall. Cell walls are assembled by a complex intracellular trafficking machinery that delivers cell wall components and their associated biosynthetic machinery to different subcellular regions.

We have recently discovered that a trafficking route directed to cell edges is essential for cell wall assembly and directional growth at the cell and organ scale. Edge-based growth regulation is independent of oriented cellulose deposition, the central paradigm of directional growth control in plants. Based on our latest data, we now propose that morphogenesis is controlled by a signalling module at cell edges which integrates feedback from the cell wall. We propose that a receptor-like protein recently identified as the first known cargo of edge-directed trafficking acts as a core component of a cell wall signalling module at edges. This hypothesis provides a mechanistic explanation for the role of cell edges as integrators of cell and tissue-level mechanical factors into coordinated cell wall assembly.