Frank Uhlmann 's Mechanisms Behind The Cleavage Of Protein
708 Words3 Pages
In this review article that I picked to write about, Frank Uhlmann reviewed numerous mechanisms behind the cleavage of protein subunits on the cohesion complex, which is accomplished by a site-specific protease we now call separase. He explained the importance of the cohesion complex, controlling separase and why the mechanisms are essential to the separation of the sister chromatids.
I chose to write about this topic specifically, because I found mitosis even more interesting than what I initially learned about many years ago. When I learned that there was a particular mechanism behind the separation of the sister chromatids, I wanted to have a better understanding of what specific proteins are involved, how they are important to the cell cycle, and what could happen to the overall cell if one of those proteins which were involved with the separation of the sister chromatids were not made or the cell made too much. Furthermore, understanding this topic is important to genetics because according to Uhlmann, if there is an error in the distribution of the chromosomes, then the end result is aneuploidy. Aneuploidy is when there is a presence of too many or not enough chromosomes inside the cell. The effects of aneuploidy show results in birth defects and cancers. This knowledge of how chromosome are distributed, will help me to have a better understanding of the transference of traits, and which mutations are the result of how the chromosomes are distributed.
In prophase, the chromosomes prepare to move to the metaphase plate by coiling and condensing. The cohesion complex also holds the sister chromatids together. The cohesion complex that holds the sister chromatids together at the centromeric region is made up of...
... middle of paper ...
...tion through the process of ubiquitylation, with the purpose of binding of an ubiquitin protein onto a substrate protein. Securins are regulators of separase proteins. They bind and inhibit separase until securin is degraded; as a result, separase is free to cleave cohesion.
Separase is a site-specific protease enzyme that is used to cleave the Scc1 subunit on the cohesion complex. Once separase cleaves the cohesion complex that includes Scc1 and Scc3 subunits; the forces of the mitotic spindle start to separate the sister chromatids, eventually causing them to move to opposite poles of the cell. The mechanisms that cleave these proteins are understandably permanent and cannot be reversed. Therefore, the cell cycle ensures to meticulously observe other mechanisms that are going on simultaneously with the aim to prevent these cells from continuing on into anaphase.