| Definition: |
A cytoskeletal structure composed of actin filaments, myosin, and myosin-associated proteins that forms beneath the plasma membrane of many cells, including animal cells and yeast cells, in a plane perpendicular to the axis of the mitotic spindle, i.e. the cell division plane. Ring contraction is associated with centripetal growth of the membrane that divides the cytoplasm of the two future daughter cells. In animal cells, the mitotic contractile ring is located inside the plasma membrane at the location of the cleavage furrow. In budding fungal cells, e.g. mitotic S. cerevisiae cells, the mitotic contractile ring forms beneath the plasma membrane at the mother-bud neck before mitosis. |