Identification and Interaction Between Centrosomal Protein Centriolin and the E3 Ubiquitin Ligase, HECTD1

Abstract

Uncontrolled cellular division is a central hallmark of cancer. Thus, studying the molecular functions and interactions of the proteins that regulate the complex processes of cell division is crucial. Two proteins are at the focal point of this study. One is centriolin, a 270 kD protein that has been demonstrated as essential for cytokinesis. The second is a 289 kD E3 ubiquitin ligase called HECTD1. Prior experiments utilizing a yeast two hybrid screen concluded that there is an interaction between centriolin and HECTD1. Furthermore, results of immunoprecipation and western blot from synchronized cells showed that centriolin was diminished in G0, whereas HECTD1 levels were elevated compared to other phases of the cell cycle. In contrast, centriolin concentrations were much more robust in S phase, G1, and M phases, compared to that of G0. In separate experiments, we have used CRISPR to eliminate either centriolin or HECTD1 in HeLa cells to observe the repercussions of the loss of these proteins and their global effects on the cell cycle. Interestingly, we observed significant cell death when we eliminated the HECTD1 gene. Our further experiments revealed that the cell death is due to robust induction of apoptosis. Currently we are investigating whether or not the established interaction between centriolin and HECTD1 plays a role in the cell death that we observed.Support or Funding InformationThis research was supported by Lincoln Memorial University‐DeBusk College of Osteopathic Medicine Intramural Grant.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.