Effect of Alternative Splicing Euchromatic Histone Lysine Methyltransferase 2 (EHMT2/G9A) on Spermatogenesis in Mongolian Horses

The epigenetic regulation of gene expression through the covalent modification of histones is crucial for developing germline cells. To study the regulatory role of alternative splicing (AS) of euchromatic histone lysine methyltransferase 2 (EHMT2/G9A) in spermatogenesis in Mongolian horses, this study first examines the localization of the <i>EHMT2</i> gene in testicular support cells and then predicts the higher-order structures of sequences with and without AS. Two types of lentiviral vectors for overexpression were subsequently constructed for the <i>EHMT2</i> gene, one with AS and one without, to infect support cells. The proliferation and activity of infected cells were measured using CCK8, and the differential expression of spermatogenesis-related genes in the two types of support cells was analyzed via qRT-PCR. We analyzed the expression of <i>EHMT2</i> by immunofluorescence staining. <i>EHMT2</i> was expressed in the nuclei of Sertoli cells. The expression of spermatogenesis-related genes was measured in the two types of cells. The results reveal that the expression levels of the <i>FSH</i>, <i>Stra8</i>, <i>CCNB2</i>, <i>CDC27</i>, <i>NRG1</i>, <i>PPP2R5C</i>, <i>CCNB2</i>, and <i>YWHAZ</i> genes in the AS group were greater than those in the control group. These results indicate that AS events in <i>EHMT2</i> affect gene expression and thus affect spermatogenesis.