Determining the Role of the XRHAMM Protein During Microtubule Nucleation and Cancer Progression

Abstract

Cancers progress as a result of hyper cell proliferation, and in order for cells to divide so often, they need extra cell division machinery to do so. It has recently been found that in cancer cells, the receptor for hyaluronan-mediated motility (RHAMM) is overexpressed, and that its homolog in Xenopus laevis is also involved in microtubule (MT) nucleation of spindle microtubules—a direct link to cell division since MTs segregate chromosomes before cytokinesis. Although much is known about branching microtubule nucleation in X. laevis, but the precise role that RHAMM plays in Xenopus (XRHAMM) is yet to be discovered. In this study, I seek to learn more about XRHAMM in order to apply these findings to uncover how this protein functions in cancers. To do this, I constructed plasmids containing the N- and C-terminal fragments of XRHAMM via Gibson Assembly. Furthermore, I performed a 2 L expression of XRHAMM primer dimers tagged with GFP, Strep, and Histidine, along with a 50 mL test expression of the N- and C-terminal constructs of XRHAMM. Future directions of this research may go on to purify the Full Length XRHAMM, along with TPX2, ɣ-Tubulin Ring Complex, and NEDD1, and perform biochemical assays on these components to see if they form a complex in vitro, as previous studies have suggested from in vivo experiments. The function of XRHAMM may also be analyzed in processes such as branching microtubule (MT) nucleation with the intention of better understanding its function in cell division of human RHAMM. Insights from this project and others like it may further the field’s understanding of XRHAMM, branching MT nucleation, and possible cancer therapies that might directly target XRHAMM or any of its functions or interaction partners.