Symmetry-breaking of animal cytokinesis

Cytokinesis is a mechanism that separates dividing cells via constriction of a supramolecular structure, the contractile ring. In animal cells, three modes of symmetry-breaking of cytokinesis result in unilateral cytokinesis, asymmetric cell division, and oriented cell division. Each mode of cytokinesis plays a significant role in tissue patterning and morphogenesis by the mechanisms that control the orientation and position of the contractile ring relative to the body axis. Despite its significance, the mechanisms involved in the symmetry-breaking of cytokinesis remain unclear in many cell types. Classical embryologists have identified that the geometric relationship between the mitotic spindle and cell cortex induces cytokinesis asymmetry; however, emerging evidence suggests that a concerted flow of compressional cell-cortex materials (cortical flow) is a spindle-independent driving force in spatial cytokinesis control. This review provides an overview of both classical and emerging mechanisms of cytokinesis asymmetry and their roles in animal development.

Automated summary

Cytokinesis is a mechanism that separates dividing cells using a supramolecular structure called the contractile ring. The symmetry-breaking modes of cytokinesis, including unilateral cytokinesis, asymmetric cell division, and oriented cell division, play important roles in tissue patterning and morphogenesis. While the classic mechanism involves the geometric relationship between the mitotic spindle and cell cortex, emerging evidence suggests that a concerted flow of compressional cell-cortex materials can also drive spatial cytokinesis control.