Saint, R.Somers, W.2008-09-262008-09-262003Journal of Cell Science, 2003; 116(21):4277-42810021-95331477-9137http://hdl.handle.net/2440/47801Despite a century of research into the nature of animal cell division, a molecular explanation for the positioning of the actomyosin contractile ring has remained elusive. The discovery of a novel interaction between regulators of Rho family small GTPases has revealed a link between the mitotic microtubules and the contractile ring during the later stages of mitosis. The properties of the interacting Rho regulators suggest a molecular model for the positioning and initiation of contractile ring furrowing in animal cells. In this ‘double ring’ model, centralspindlin complexes, localized by the action of their kinesin-like protein component, position and activate a cortical equatorial ring of Rho GTPase exchange factors. The resulting ring of activated Rho would then trigger a cascade of events leading to formation and constriction of the contractile ring.enCytokinesisRho GTPasePBL/Ect2 RhoGEFContractile ringPAV-KLP/MKLP1Central spindleMicrotubulesJournal article00200825892008092615255810.1242/jcs.008160001873953000032-s2.0-024246752742059