Probing the Functional Role of H2A Variant, HTZ-1, in Successful C. elegans Gamete Production
Author: Keiko Hokeness
Faculty Supervisor: Diana Chu
Department: Biology
Caenorhabditis elegans have specialized germlines for generating oocytes and sperm. Successful gamete production requires highly controlled regulation of genes, commonly involving histone variants. C. elegans possess three variants of canonical H2A including conserved HTZ-1. We aim to characterize how HTZ-1’s function in gamete production differs between sexes. We isolated germline tissues from hermaphrodite and male organisms to create differential expression profiles. Preliminary analysis of hermaphrodite germlines revealed HTZ-1 as a transcriptional activator and repressor of oogenesis-specific genes. Interestingly, we found HTZ-1 imparts a major repressive role on sperm genes, suggesting the variant may function to halt sperm generation prior to oocyte production. We question the extent to which HTZ-1 function will differ in male germlines where the germline produces sperm exclusively. We hypothesize HTZ-1 functions to increase transcription levels, consistent with ChIP-Seq analysis showing variant incorporation at promoter regions. Analysis of both hermaphrodite and male germlines will reveal if HTZ-1 function is sex-specific and expand the knowledge of H2A variant regulatory mechanisms. Moreover, we will probe the most differentially expressed genes in both germlines for enriched GO terms. This will enhance our understanding of HTZ-1’s sex-dependent role by elucidating the functions of the regulated genes in each type of germline.