Saint, RobertSomers, W Gregory2015-12-132015-12-130021-9533http://hdl.handle.net/1885/74905Despite 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.Keywords: actin; guanosine triphosphatase; kinesin; myosin adenosine triphosphatase; regulator protein; Rho factor; animal cell; article; cell division; complex formation; cytokinesis; embryo; medical research; microtubule; mitosis; molecular model; nonhuman; prior Central spindle; Contractile ring; Cytokinesis; Microtubules; PAV-KLP/MKLP1; PBL/Ect2 RhoGEF; Rho GTPase200310.1242/jcs.008162015-12-11