Cell Division Essay

Division of pre-existing cells is the only way through which new cells can come into being. For duplication of cells to happen, the genetic materials inside the cells have to duplicate first. During the S phase of the cell cycle, the chromosomes of the cells as well as the chromatin proteins duplicate. During the M phase, spindle fibers are formed, and the duplicated chromosomes arrange themselves in the equatorial region of the cells forming a metaphase plate. Mitotic spindles are formed by the centrosome present at two poles of the cells. These spindle arrays then pull each sister chromatid to the opposite sides of the cells. After this the whole cell is divided into two by undergoing cytokinesis. Segregation of chromosomes to two opposite poles of the cell is important part of cell division because unequal number of chromosomes on either side can lead to …show more content…
When Murata-Hori used a negative mutant form of Aurora-B kinase, they noticed that the movement of chromosomes was abnormal (Murata-Hori & Wang, 2002). With the mutant form, the chromosomes was seen to be arranged into two elongated bundles on the sides of the spindle axis instead of forming a metaphase plate in the equatorial region of the cell (Murata-Hori & Wang, 2002). Since the mutant used was kinase-inactive, there were a number of other adverse effects seen. When this mutant was overexpressed, motor proteins such as dynein and CENP-E were not able to function (Murata-Hori & Want, 2002). Also, the kinetochores were unable to attach to the spindle arrays (Murata-Hori & Want, 2002). These effects were more adverse, which suggests that the phosphorylating activity of the Aurora-B kinase is very important for the proper segregation of chromosomes during