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Abstract

Cytokinesis is the mechanical process that allows the simplest unit of life, the cell, to divide, propagating itself. To divide, the cell converts chemical energy into mechanical energy to produce force. This process is thought to be active, due in large part to the mechanochemistry of the myosin-II ATPase. The cell's viscoelasticity defines the context and perhaps the magnitude of the forces that are required for cytokinesis. The viscoelasticity may also guide the force-generating apparatus, specifying the cell shape change that results. Genetic, biochemical, and mechanical measurements are providing a quantitative view of how real proteins control this essential life process.

Dictyostelium huntingtin controls chemotaxis and cytokinesis through the regulation of myosin II phosphorylation

“…We identified cells in telophase based on cell morphology with the short-to-long axis ratio of 0.2 and observed them until cytokinesis was completed (Robinson and Spudich, 2004; Uyeda and Nagasaki, 2004). In wild-type cells, GFP-myosin II showed ∼80% stronger intensity at the cleavage furrow until the completion of cytokinesis compared with the polar cytoplasm (Figure 5, A and B), consistent with previous reports (Nagasaki et al , 2002; Robinson et al , 2002). In contrast, although myosin II initially accumulated in the cleavage furrow in cells with the short-to-long axis ratio of 0.2, it was gradually lost as cytokinesis progressed, and the short-to-long axis ratio became 0.1 and zero in htt − cells (Figure 5, A and B).…”

The novel RacE-binding protein GflB sharpens Ras activity at the leading edge of migrating cells

“…Dictyostelium cells divide using two distinct mechanisms. Although Dictyostelium cells mainly use the contractile ring consisting of actin and myosin II filaments in suspension culture, they also divide by traction force, which is independent of actin-myosin, on solid substrates ( Robinson et al. , 2002 ).…”

Orchestrating vesicle transport, ESCRTs and kinase surveillance during abscission

“…The best example was the slime mold, Dictyostelium discoideum . The term used for cell separation in Dictyolstelium was cytofission, the process of crawling apart and breaking the interconnection between the two cells 40 . However, recent evidence shows that even cytofission is controlled by a set of genes and that disruption of these genes blocks abscission.…”