Plastin and spectrin cooperate to stabilize the actomyosin cortex during cytokinesis

• DOI: 10.1016/j.cub.2021.09.055
• Publication Date: 2021-10-19T06:38:03Z
• Authors: Ana Filipa Sobral; Fung-Yi Chan; Michael J. Norman; Daniel S. Osório; Ana Beatriz Dias; Vanessa Ferreira; Daniel J. Barbosa; Dhanya Cheerambathur; Reto Gassmann; Julio Monti Belmonte; Ana Xavier Carvalho
• Keywords: Cell Cortex; EPB41; Formins

Cytokinesis, the process that partitions mother cell into two daughter cells, requires assembly and constriction of an equatorial actomyosin network. Different types non-motor F-actin crosslinkers localize to network, but their functional contribution remains poorly understood. Here, we describe a synergy between small rigid crosslinker plastin large flexible spectrin in C. elegans one-cell embryo. In contrast single inhibitions, co-inhibition βH-spectrin (SMA-1) results cytokinesis failure due progressive disorganization eventual collapse Cortical localization dynamics non-muscle myosin II co-inhibited embryos mimic those observed after drug-induced depolymerization, suggesting combined action stabilizes contractile ring. An silico model predicts is more efficient than at stabilizing ring formation relatively insensitive length, which confirmed vivo with sma-1 mutant lacks 11 its 29 repeats. Our findings provide first evidence contributes highlight importance interplay for network integrity.