Robo recruitment of the Wave regulatory complex plays an essential and conserved role in midline repulsion

eLife

Greg J Bashaw¹  Madhavi Gorla¹  Karina Chaudhari¹  Chao Chang²  Artur Kania² 

[1] Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States;Institut de recherches cliniques de Montréal (IRCM), Montréal, Canada;Department of Anatomy and Cell Biology and Division of Experimental Medicine, McGill University, Montréal, Canada;

关键词: axon guidance;    spinal cord;    midline;    Slit;    Robo;    wave regulatory complex;    Chicken;    D. melanogaster;    Mouse;   

DOI  :  10.7554/eLife.64474

来源: eLife Sciences Publications, Ltd

【 摘 要 】

The Roundabout (Robo) guidance receptor family induces axon repulsion in response to its ligand Slit by inducing local cytoskeletal changes; however, the link to the cytoskeleton and the nature of these cytoskeletal changes are poorly understood. Here, we show that the heteropentameric Scar/Wave Regulatory Complex (WRC), which drives Arp2/3-induced branched actin polymerization, is a direct effector of Robo signaling. Biochemical evidence shows that Slit triggers WRC recruitment to the Robo receptor’s WRC-interacting receptor sequence (WIRS) motif. In Drosophila embryos, mutants of the WRC enhance Robo1-dependent midline crossing defects. Additionally, mutating Robo1’s WIRS motif significantly reduces receptor activity in rescue assays in vivo, and CRISPR-Cas9 mutagenesis shows that the WIRS motif is essential for endogenous Robo1 function. Finally, axon guidance assays in mouse dorsal spinal commissural axons and gain-of-function experiments in chick embryos demonstrate that the WIRS motif is also required for Robo1 repulsion in mammals. Together, our data support an essential conserved role for the WIRS-WRC interaction in Robo1-mediated axon repulsion.

【 授权许可】

CC BY