Development and evaluation of a whole cell 3d and 2d kinetochore position algorithm and analyzing the role of hset, cenp-e, and kid in chromosome congression

Chromosome congression and segregation are two key events during mitosis. Congression involves the movement of chromosomes to the spindle equator, and this movement is coordinated by the attachment of microtubules to the chromosomes. Although there are several congression mechanisms that have been proposed, mechanistic details of these proposed mechanisms remain incomplete. Generally, congression represents a fast-paced and highly regulated event that takes approximately 10 min in human cells. To better understand the mechanisms involved, a kinetochore position algorithm has been developed using Imaris software. To evaluate the ability of this algorithm to detect kinetochore positions, hNuf2- and Cenp-E-targeted siRNA were transfected into HeLa cells and the resulting kinetochore positions were detected and analyzed. To investigate the roles of HSET, Cenp-E, and Kid motor proteins during congression, individual or combined RNAi targeting of the corresponding genes were performed. The role of Cenp-E in K-fiber independent kinetochore positioning was analyzed. In these studies, Cenp-E, K-fibers, and end-on attachments were absent and HSET was present, and congression still occurred in bipolar spindles. Additional studies will be needed to further elucidate the mechanistic details and proteins that mediate congression. However, it is apparent that redundant congression mechanisms exist in order to ensure that this critical event can occur without errors to ensure the survival of an organism.