THE TWO ISOFORMS OF UGGT ARE DIFFERENTIALLY EXPRESSED DURING MOUSE MAMMARY GLAND DEVELOPMENT

ACOSTA AG; SANTILLAN ZABALA V.J; KORDON E; MIRANDA S; CASTRO OA

Mar del Plata

Congreso; LI Annual Meeting of the Argentine Society for Biochemistry and Molecular Biology; 2015

Sociedad Argentina de Investigación Bioquímica y Biología Molecular

THE TWO ISOFORMS OF UGGT ARE DIFFERENTIALLY EXPRESSED DURING MOUSE MAMMARY GLAND DEVELOPMENT Acosta AG1 ; Santillán VJ1 ; Kordon EC2 ; Miranda SE3 , Castro OA1,4. 1 IQUIBICEN (CONICET-UBA) 2 IFIBYNE (CONICET-UBA), 3 ININCA (CONICET-UBA) 4 FBMC/FCEN/UBA. E-mail: gabyacosta2456@hotmail.com UGGT (UDP-Glc::glycoprotein glucosyltransferase) is the key component of the quality control mechanism of glycoprotein folding. There are two isoforms of UGGTs (UGGT-1 and UGGT-2) in vertebrates and nematodes and both of them showed canonical UGGT activity in in vitro assays, but it seems that they play different biological functions. As previous results showed that progesterone regulates the expression and the activity of the two UGGTs isoforms in a mouse hybridoma, we decided to analyze if these enzymes were hormonally regulated during mammary gland development. We determined by qPCR the level of expression both isoenzymes in mammary glands of C57/BL6 mice in different stages: virgin, pregnant, breastfeeding, post-lactational involution 24 h, 48 h and 72 h after weaning, and found that both enzymes were differentially regulated. The expression of uggt1 was higher than uggt2 during breastfeeding and mammary involution; but in virgin and pregnant mice uggt2 expression levels were at least 2 fold higher than that of uggt1. Pregnant mice have increasing levels of circulating progesterone along pregnancy; we analyzed the expression of both enzymes at day 7, 15 and 17 and results showed a correlation between uggt-2 expression and progesterone level. We also treated T47D cells for 24 h with increasing concentrations of progesterone and found that uggt2 expression is also regulated by progesterone.