title: Proper positioning of the cleavage furrow requires α-actinin to regulate the specification of different populations of microtubules.
abstract: Proper positioning of the cleavage furrow is essential for successful cell division. The mitotic spindle, which consists of dynamic astral microtubules and stable equatorial microtubules is responsible for this process. However, little is known about how microtubules are regulated in a time- and region-dependent manner. Here, we show that α-actinin-regulated cortical actin filament integrity is crucial to specify different populations of microtubules during cell division in mammalian cells. Depletion of α-actinin caused aberrant recruitment of centralspindlin, but not aurora B or PRC1, to the tips of astral microtubules, leading to a stable association of astral microtubules with the cortex and induction of ectopic furrowing. Depletion of α-actinin also caused impaired assembly of midzone microtubules, leading to a failure of relocation of aurora B to midzone. Our findings unveil an unexpected yet crucial role for an actin crosslinking protein in the regulation of the localization of the microtubule-associated cytokinetic regulator.
authors: Cell Biology Program, Temasek Life Sciences Laboratory, The National University of Singapore, Singapore.
authors: Vinayaka
authors: V
authors: Srinivas
authors: Maki
authors: M
authors: Murata-Hori
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism / Q000648:ultrastructure; D000185:Actinin / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D064107:Aurora Kinase B; D064127:Aurora Kinases; D018797:Cell Cycle Proteins / Q000235:genetics* / Q000378:metabolism*; D002455:Cell Division / Q000235:genetics; D006367:HeLa Cells; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000235:genetics* / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism / Q000648:ultrastructure; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D008941:Spindle Apparatus / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D020742:rhoA GTP-Binding Protein / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D018797:Cell Cycle Proteins; D008869:Microtubule-Associated Proteins; D034741:RNA, Small Interfering; D000185:Actinin; C066737:RHOA protein, human; C576921:AURKB protein, human; D064107:Aurora Kinase B; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases; D020742:rhoA GTP-Binding Protein