Lentivirus-mediated in vivo Gpat2-silencing in mouse testis impairs spermatogenesis

GARCIA FABIANI MARIA BELEN; STRINGA, PABLO; CATTANEO, ELIZABETH; LOFEUDO, JUAN MANUEL; LACUNZA, EZEQUIEL; PELLON MAISON MAGALI; MONTANARO, MAURO ALDO; GONZALEZ BARO, MARIA DEL ROSARIO

Congreso; L Reunión Anual de la Sociedad Argentina de Investigación Bioquímica y Biología Molecular; 2014

We have previously shown that the isoform 2 of glycerol-3-phosphate acyltransferase (GPAT2), an enzyme belonging to the GPAT family that has unique expression characteristics compared to the other members (GPAT1, 3, and 4), is expressed almost exclusively in spermatic cells. We have further confirmed GPAT2 as a member of the cancer-testis group of genes having an abnormal overexpression in certain tumor cell types and DNA-methylation-mediated transcription regulation. To understand the role of GPAT2 in relation to spermatic cell maturation and the spermatogenic process, we studied the age dependent expression profile of mouse GPAT2 by Q-PCR and Western blot. We found an expression peak at post natal day (PND) 15. We confirmed these results by immunohistochemistry and in situ hybridization, and observed that GPAT2 is localized preferentially in pachytene spermatocytes and not in spermatogonia. We then performed an in vivo lentivirus-mediated silencing of GPAT2 in mouse testis. Histological and immunohistochemical analysis showed both a strong post-meiotic arrest and a severe decrease in the number of mature sperm cells in those tubules with diminished GPAT2 protein expression. These results show that GPAT2 is important for the normal progress of the spermatic cycle in post-natal testis development.