INVESTIGADORES
GONZALEZ BARO Maria Del Rosario
congresos y reuniones científicas
Título:
Lipid synthesis in testis: GPAT2 activity and expression
Autor/es:
CATTANEO, E.R.; PELLON-MAISON, M.; BRENNER, R.R.; COLEMAN, R.A.; GONZALEZ-BARO, M.R.
Lugar:
Mar del Plata, Argentina
Reunión:
Congreso; XLIII Reunión Anual de la Sociedad Argentina de Investigación Bioquímica (SAIB); 2007
Institución organizadora:
Sociedad Argentina de Investigacion Bioquimica y Biologia Molecular
Resumen:
Four different isoforms of glycerol-3-phosphate acyltransferase
have been described in mammalian cells. GPATs 1 and 2 are located
in the mitochondria. GPAT2 is sensitive to sulfhydryl reagents
(NEM), has no acyl-CoA substrate preference and was first
recognized in liver from GPAT1 null mice. GPAT2 cDNA cloned
from mouse testis encodes a protein of 797 aa (89 kDa) and 27% aa
identity to GPAT1. Because GPAT2 mRNA expression was very
high in testis, the aim of this study was to characterize the GPAT2
activity in highly purified mitochondria from wild type mouse and
rat testis. The purity of the subcellular fractions was confirmed by
marker enzymes and proteins. For the first time, NEM-sensitive
GPAT activity was detected in purified mitochondria from wild type
mouse and rat testes.We assume that this activity corresponds to the
GPAT2 isoform because GPAT2 mRNA expression was more than
10 times higher in testis than in any other tissue. Although GPAT1
mRNAwas 5-fold higher in liver than in testis, NEM-resistantGPAT
activity in testis was 3-fold higher than in purified mitochondria
from liver. In contrast, GPAT2 mRNA was 50-fold higher in testis
than in liver, and, consistently, the NEM-sensitive activity in
purified mitochondria was high in testis and was not detectable inliver.