Septum (cell biology)

[2] Ultimately, the septum is the crucial ending to mitosis, meiosis, and the division of bacterial cells.

[4] This protein machinery works to form the barrier known as the septum between the two daughter cells.

[4] The Z-ring formation is made possible due to certain positioning proteins that depend on the species of the cell.

[4] Once the proto-ring is assembled, FtsA (the ancestor to actin for bacteria) connects the Z ring to the other proteins within the divisome and the constriction of the Z-ring and cytoplasmic membrane begins inward.

[6] This cleavage furrow is able to pinch together due to the actin filaments that form the contractile ring.

[6] Thus, in animal cells it can be observed that the septum is not a true wall, rather the pinching of a cleavage furrow.

After degradation of the primary septum, a chitinous bud scar remains on both the mother and daughter cell.

[10] For instance, if the cleavage furrow in an animal cell fails to cleave inwards due to the absence of one of its activators such as polo-like kinase 1, the cell remains with double the amount of chromosomes and could lead to cancerous tumors.