Untying the gordian knot of cytokinesis: Role of small G proteins and their regulators

Ability to divide is one of the basic properties of a cell. In metazoans, where cells divide in a context of germ layers, tissues, and organs, cell proliferation must be coordinated with differentiation to prevent developmental abnormalities. Genetic analyses in simple model systems (yeast, slime mold, fruit fly) have demonstrated that defects in either karyokinesis, or nuclear division (e.g., mutations that affect cell cycle checkpoints, mitotic chromosome condensation and segregation, etc.), or cytokinesis (Fig. 1), both may delay or block development.