Which protein is essential for cytokinesis in animal cells?
Animal cytokinesis culminates mitosis by physically partitioning cytoplasm through contractile ring machinery. Following chromosome segregation, central spindle composed of overlapping antiparallel microtubules bundled by PRC1 and motor KIF4 recruits centralspindlin complex containing kinesin MKLP1 and RhoGAP MgcRacGAP which tethers ECT2 guanine nucleotide exchange factor to equatorial cortex, generating localized accumulation of active RhoA-GTP. RhoA stimulates formin mDia1 to nucleate linear actin filaments and activates ROCK kinase to phosphorylate myosin regulatory light chain at serine 19
Ref: Glotzer, Science 2005, Cytokinesis Mechanisms. Alberts 7th ed., Chapter 17, Contractile Ring.
