centralspindle

The centralspindle is a transient structure that forms during cytokinesis, the process of cell division. It is located in the equatorial region of the dividing cell, between the two nascent daughter cells. The centralspindle is primarily composed of microtubules and associated motor proteins, such as kinesins and dyneins.

The formation of the centralspindle is a critical step in ensuring that the cell divides into two genetically identical daughter cells. It plays a role in establishing the plane of cell division and in the abscission of the two daughter cells. The centralspindle acts as a scaffold, guiding the ingression of the cell membrane to physically separate the cytoplasm.

During anaphase, the chromosomes have segregated to opposite poles of the cell. As the cell enters telophase, the centralspindle begins to assemble. Microtubules emanating from the spindle poles overlap in the midzone of the cell, forming the characteristic barrel-like structure of the centralspindle. Motor proteins then work to slide these microtubules past each other, contributing to the elongation of the cell and the formation of the cleavage furrow.

The precise regulation of centralspindle assembly and disassembly is crucial for successful cytokinesis. Defects in centralspindle formation or function can lead to aneuploidy, where daughter cells have an abnormal number of chromosomes, or to cytokinesis failure, resulting in multinucleated cells. Research into the centralspindle continues to shed light on the fundamental mechanisms of cell division and its implications in development and disease.