KATANIN and CLASP function at different spatial scales to mediate microtubule response to mechanical stress in Arabidopsis cotyledons

• DOI: 10.1016/j.cub.2021.05.019
• Publication Date: 2021-06-08T14:29:57Z
• Authors: Ryan C. Eng; René Schneider; Timon W. Matz; Ross Carter; David W. Ehrhardt; Henrik Jönsson; Zoran Nikoloski; Arun Sampathkumar
• Keywords: 0301 basic medicine; Arabidopsis Proteins; mechanical stress; Arabidopsis; morphogenesis; cytoskeleton; pavement cells; Microtubules; cell shape; live-cell imaging; microtubules; 03 medical and health sciences; morphology; Stress, Mechanical; Katanin; Cotyledon; Microtubule-Associated Proteins; mechano-response

Mechanical stress influences cell- and tissue-scale processes across all kingdoms. It remains challenging to delineate how mechanical stress, originating at these different length scales, impacts cell and tissue form. We combine growth tracking of cells, quantitative image analysis, as well as molecular and mechanical perturbations to address this problem in pavement cells of Arabidopsis thaliana cotyledon tissue. We show that microtubule organization based on chemical signals and cell-shape-derived mechanical stress varies during early stages of pavement cell development and is mediated by the evolutionary conserved proteins, KATANIN and CLASP. However, we find that these proteins regulate microtubule organization in response to tissue-scale mechanical stress to different extents in the cotyledon epidermis. Our results further demonstrate that regulation of cotyledon form is uncoupled from the mechanical-stress-dependent control of pavement cell shape that relies on microtubule organization governed by subcellular mechanical stress.