GLYCEROL-3-PHOSPHATE ACYLTRANSFERASE 2 IS EXPRESSED IN SPERMATOCYTES AND UNDIFFERENTIATED CANCER CELLS

PELLON-MAISON M; CATTANEO, ER; COLEMAN, RA; GONZALEZ-BARO, MR

Puerto Madryn

Congreso; XLVI Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB); 2010

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

The first step in the de novo glycerolipid biosynthesis is catalyzed by glycerol-3-phosphate acyltransferase (GPAT). Four genes encoding GPATs have been cloned; Gpat2 encode a protein mainly expressed in rat, mouse and human testis. Previously, we have shown that Gpat2 overexpression in CHO-K1 cells increased 14C-oleate esterification into triacylglycerol, the area of the lipid droplets, and cell proliferation. In this work we quantified by qPCR Gpat2 expression in 3T3-L1 cells subjected to differentiation to adypocite. This experiment showed that Gpat2 is not induced upon differentiation to adypocite. This results is consistent with the in silico analysis of transcriptomes, which show that Gpat2 is downregulated in different models of cell differentiation. Moreover, we determine by in situ hybridization that Gpat2 is expressed exclusively in spermatocytes in mouse testis, and the expression dramatically decline when cells enters in meiotic and differentiation phases. Gpat2 was included in cancer-testis genes database. In this work we detected by RT-PCR Gpat2 expression in MDA-MB 231 cells, a breast cancer undifferentiated cells line. Labelling experiments were performed with 14C-arachidonate in Gpat2 overexpressing cells. At 3 hours of incubation there was an increase in radioactive TAG and a decrese in radioactive PC and PE. At 6 and 24 hour there was a significant increase in radioactive lysophosphatidilcoline. The results suggest that some metabolites derived from GPAT2 activity contribute to cell proliferation and survival