Panagiotou Thomas C, Chen Anan, Wilde Andrew
Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1M1, Canada.
Department of Biochemistry, University of Toronto, Toronto, ON M5S 1M1, Canada.
Cell Rep. 2022 Aug 30;40(9):111274. doi: 10.1016/j.celrep.2022.111274.
Cleavage of one cell into two is the most dramatic event in the life of a cell. Plasma membrane fission occurs within a narrow intercellular bridge (ICB) between the daughter cells, but the mechanisms underlying ICB formation and maturation are poorly understood. Here we identify CIN85 as an ICB assembly factor and demonstrate its requirement for robust and timely cytokinesis. CIN85 interacts directly with the N-terminal region of anillin and SEPT9 and thereby facilitates SEPT9-containing filament localization to the plasma membrane of the ICB. In contrast, the C-terminal pleckstrin homology (PH) domain of anillin binds to septin units lacking SEPT9 but enriched in SEPT11. Anillin's interactions with distinct septin units are required to promote ICB elongation and maturation that, we propose, generate the physical space into which the abscission machinery is recruited to drive the final membrane scission event releasing two independent daughter cells.
一个细胞分裂为两个细胞是细胞生命中最显著的事件。质膜裂变发生在子细胞之间狭窄的细胞间桥（ICB）内，但ICB形成和成熟的潜在机制仍知之甚少。在这里，我们确定CIN85为ICB组装因子，并证明其对稳健且及时的胞质分裂的必要性。CIN85直接与锚蛋白和SEPT9的N端区域相互作用，从而促进含SEPT9的细丝定位于ICB的质膜。相反，锚蛋白的C端普列克底物蛋白同源（PH）结构域与缺乏SEPT9但富含SEPT11的septin单元结合。我们认为，锚蛋白与不同septin单元的相互作用对于促进ICB的伸长和成熟是必需的，这会产生一个物理空间，细胞分裂机制被招募到该空间以驱动最终的膜分裂事件，从而释放出两个独立的子细胞。
