THE ROLE OF RHOX5 AND RHOX8 IN MALE FERTILITY

Homeobox proteins are transcription factors that play key roles in the process of embryogenesis. Here we study two genes, the Rhox5 and Rhox8 that belong to a subfamily of Homeobox genes, the reproductive homeobox genes. The study account the knowledge of gene regulatory network under the control of Rhox8. We report the de novo DNA binding motifs of RHOX8 in the Sertoli cells of the male mice testis and the granulosa cells of the female mice ovary, the biological processes, molecular functions and the cellular components under the regulation of Rhox8 gene both in the Sertoli cells and the granulosa cells, and predict the nature of RHOX8 binding to its DNA motif. The study also reveals that the subfertility exhibited by the Rhox5-null male mice is not related to any defects in the ability of the sperm to capacitate, thereby reiterating that the phenotypic subfertility of the Rhox5-null mutants is due to low sperm count and decrease in forward motility as reported in earlier studies. We also confirm the allelic deletions of Rhox5 and Rhox8 genes and check their protein expression through western blots in the new double knockout and respective single knock out mutants developed using the latest CRISPR/Cas9 technology. Finally, we developed a staining prototype using the fat-soluble diazo dye, Sudan Black B to reduce undesirable intrinsic autofluorescence of Leydig cells in mouse testis crosssections for improved visualization of multiple autofluorescent signals