INVESTIGADORES
MIRANDA Silvia Esther
congresos y reuniones científicas
Título:
The expression of both isoforms of UGGT are differentially regulated in T47D cells by Progesterone and in mammary gland development during mouse pregnancy
Autor/es:
ACOSTA-MONTALVO G; RIAL HAWILA MR; KORDON E; MIRANDA S; CASTRO OA
Lugar:
CABA
Reunión:
Congreso; III International Congress in Translational Medicine; 2016
Institución organizadora:
Facultad de Farmacia y Bioquímica UBA
Resumen:
UGGT (UDP-Glc::glycoprotein glucosyltransferase), which has the ability to discriminate folded from misfolded glycoproteins, is the key component of the quality control mechanism of glycoprotein folding that ensures that only properly folded proteins exit the ER. In yeast, fly, parasites and plants an enzymatically active UGGT is encoded by a single gene whereas there are two homologues coding for UGGT-like proteins (UGGT-1 and UGGT-2) in vertebrates and in some species of nematodes. We reported that both isoforms play different biological roles in C.elegans. We showed that the uggt-2 null mutant is lethal, while the uggt-1 null mutant is only barely affected. Recently, we showed that both isoforms were differentially regulated by high doses of progesterone (P4) in a mouse hybridoma. Previous analysis of ChIP-seq datasets for PR in human mammary ductal carcinoma cell line T47D revealed that it binds uggt2 promoter at different concentrations of R5020 (10-8 M and 10-7 M). These facts suggest that the level of expression of uggt2 may be regulated by P4 in a dose dependent manner. To confirm this hypothesis, we studied the expression of both isoforms in T47D cells in the presence of increasing doses of P4. We also analyzed the level expression of both isoforms of UGGT in vivo using the mouse mammary gland during pregnancy as a physiological model. We found that the mRNA level expression of uggt1 determined by RT-qPCR in the mammary gland increases throughout pregnancy while that of uggt-2 shows an opposite pattern. Moreover, when we studied the protein pattern expression of UGGT1 and UGGT-2 in cuboid epithelial cells and in adipocytes we found that they were differentially regulated. Both isoforms peak in epithelial cells at day 15, while in adipocytes UGGT1 decreases during pregnancy and UGGT-2 levels remains constant. On the other hand, the expression of uggt1 in T47D cells culture increases as the P4 concentration raises until two fold increase at 10-5 M P4 at 24 h. Instead, the level of expression of uggt-2 diminishes up to 40 % at 10-8 and 10-7 M de P4 and we found no change respect to the control at 10 -5 M. As a summary we can conclude that both enzymes are differentially regulated by P4 in T47D cells and their expression in mammary gland showed also a different expression pattern supporting the idea that each isoform plays a different biological role.