Macroscopic stiffening of embryonic tissues via microtubules, RhoGEF and the assembly of contractile bundles of actomyosin

• DOI: 10.1242/dev.045997
• Publication Date: 2010-07-15T00:49:07Z
• Authors: Jian Zhou; Hye Young Kim; James H.-C. Wang; Lance A. Davidson
• Keywords: Nocodazole

During morphogenesis, forces generated by cells are coordinated and channeled the viscoelastic properties of embryo. Microtubules F-actin considered to be two most important structural elements within living accounting for both force production mechanical stiffness. In this paper, we investigate contribution microtubules stiffness converging extending dorsal tissues in Xenopus laevis embryos using cell biological, biophysical embryological techniques. Surprisingly, discovered that depolymerizing stiffens embryonic three- fourfold. We attribute tissue stiffening Xlfc, a previously identified RhoGEF, which binds regulates actomyosin cytoskeleton. Combining drug treatments Xlfc activation knockdown lead us conclusion such as viscoelasticity can regulated through RhoGTPase pathways rule out direct frog rescue nocodazole-induced with drugs reduce contractility partially morphogenetic defects affect stiffened embryos. support these conclusions multi-scale analysis cytoskeletal dynamics, tissue-scale traction measurements separate role from RhoGEF activation. These findings suggest re-evaluation effects nocodazole increased focus on Rho family GTPases regulators their interactions surrounding tissues.