Abstract:

During morphogenesis, mechanical forces induce cellular and tissue-wide deformations. These forces, in conjunction with cell geometry and biochemical properties, including hormones, drive the morphogenetic process. We employ regeneration in Arabidopsis thaliana as a tool to investigate morphogenesis. Our investigations, utilizing tissue culture-mediated shoot regeneration, unveil the necessity of mechanical forces in orchestrating the self-organization of shoot initials, known as progenitors, from undifferentiated callus into functional shoot meristems. To elucidate the process, we propose a stretch-compress model explaining how mechanical forces induce compression in progenitor cells and expansion in neighbouring cells. The resulting changes in cell geometry and mechanical conflicts are key to the making of a dome-shaped shoot meristem. Notably, this mechanistic module also operates in the restoration of an organ lost in injury. Using Arabidopsis root tip regeneration, we identify a similarly operating push-pull mechanistic model that facilitates the U-shaped convergence of longitudinal cell files at the regenerating tip and the repositioning of the stem cell niche (SCN). Our study underscores the significance of cell geometry and mechanochemical feedback between adjacent cells as key drivers of tissue morphogenesis.

About the speaker:

Dr. Kalika Prasad obtained his PhD from Indian Institute of Science, Bangalore. He was EMBO post doctoral fellow at Utrecht University, The Netherlands and then moved to IISER as group leader.

http://thelabofregeneration.in/Kalika_Prasad/index.html