Glycerol-3-phosphate acyltransferase 2 (GPAT2) is required for mouse spermatogenesis

GARCIA FABIANI MB; STRINGA P; CATTANEO, ER; PELLON MAISON M; HENNING F; MONTANARO MA; GONZALEZ BARÓ, MR

Mar del Plata

Congreso; LI Reunion Anual de SAIB; 2015

SAIB

Glycerol-3-phosphate acyltransferase 2 (GPAT2) differs from the other GPAT family members (GPAT1, 3, and 4);it is expressed almost exclusively in spermaticcells while the other 3 isoforms are expressed in lipogenic tissues. We have determined that mouse Gpat2 mRNAis expressed transiently in one step of spermatogenesis, the pachytene spermatocytes. To understand its transcriptional regulation, we bisulfite-sequenced the genomic DNA of male germ cells and found a global hypomethylation of Gpat2 promoter at 11 days of age, when meiosis starts, indicating that DNA methylation governs Gpat2 mRNA expression. To further understand the role of GPAT2 in spermatogenesis, we performed an in vivo lentivirus-mediated Gpat2silencing in mouse testis. Histological and immunohistochemicalanalysis showed both a strong pre-meiotic arrest and a severe decrease in the number of mature sperm cells. We studied the effect of GPAT2 on malefertility and found that the Gpat2-silenced mice showed a diminished number of birthscompared to the control mice group. Also, we studied the expression of target genes which are differentially expressed during different phases of the spermatogenesis by qPCR to determine more precisely the step where this process stops when Gpat2 is silenced. These resultsdemonstrate that GPAT2 is important for the normal progress of spermatogenesis in post-natal testis development