Anillin: a pivotal organizer of the cytokinetic machinery.
Cytokinesis is a dynamic and plastic process involving the co-ordinated regulation of many components. Accordingly, many proteins, including the putative scaffold protein anillin, localize to the cleavage furrow and are required for cytokinesis, but how they function together is poorly understood. Anillin can bind to numerous other furrow components, including F-actin, septins and myosin II, but its molecular functions are unclear. Recent data suggest that anillin participates in a previously unrecognized Rho-dependent pathway that can promote the association of anillin with the plasma membrane, septins, myosin II and microtubules. Studies using the inhibitor of F-actin assembly, Lat A (Latrunculin A), have revealed that these associations occur independently of F-actin; indeed they appear to be stabilized by the loss of F-actin. This pathway may explain previously described requirements for anillin in maintaining stable furrow positioning and for forming a stable midbody, and supports the notion that anillin is a central organizer at the hub of the cytokinetic machinery.