INVESTIGADORES
PETITI Juan Pablo
congresos y reuniones científicas
Título:
Regulatory effect of estradiol mediated by ERa palmitoylation on the proliferative activity in normal and tumoral adenohypophyseal cells
Autor/es:
SOSA L.; CHUMPEN S.; VACA A.; PICECH F.; GUIDO C.; NICOLA J.P.; PETITI J.P.; GUTIÉRREZ S.; DE PAUL A.; VALDEZ TAUBA J.; TORRES A.I.
Lugar:
Praga
Reunión:
Congreso; 12th International Congress of Cell Biology; 2016
Resumen:
Previously, we have demonstrated that estradiol (E2), through membrane estrogen receptor alpha (mERa), modulates the functional activity in adenohypophysial cells. One requirement for ER location at the plasma membrane is the presence of a hydrophobic segment as a part of the receptor structure, being reported the addition of a palmitate molecule, commonly called palmitoylation, in steroid receptors. The aim of this study was to analyze the ERa palmitoylation and their implication in E2-triggered membrane-initiated signaling in normal and tumoral pituitary cell proliferation. Adenohypophysial cells from female Wistar rats and tumoral GH3 cell were exposed to E2 (10 nM) for 30 min. Palmitoylation of REa was determined by acyl-biotin exchange method; mREa expression was evaluated by membrane proteins biotinylation and mREα and caveolin 1 (cav1) association by immunoprecipitation. Cell proliferation was analyzed by BrdU uptake and REa, cav-1 and phosphorylated and total ERK1/2 expression by WB. The palmitoylases participation was evaluated using the inhibitor 2-bromo palmitate (2BP, 10 uM) and the DHHC-7 and DHHC-21 mRNA levels were determined by qPCR after 3, 6, 9 h of E2 stimulation. Statistics: Test-t. The ERa palmitoylated was detected in normal and GH3 adenohypophysis cells. The general inhibitor of palmitoylation induced loss of mERa location and inhibited the REa/cav1 association in both cell culture conditions. In addition, E2 treatment was able to regulate DHHC-7 and -21 expressions showing a decrease in mRNA levels at 3h, reaching similar levels to control after 6h. In primary cultures, the BrdU uptake was not modified by E2 treatment, whereas ERK1/2 phosphorylation was inhibited by 2BP. In contrast, GH3 cell proliferation was stimulated after E2 treatment, data in correlation with the significant increase of ERK1/2 phosphorylation levels, effects that were inhibited by 2BP. These findings suggest that ERa palmitoylated contribute to E2 effects initiated at the plasma membrane triggering the tumoral GH3 cells proliferation and that E2 could modulate to DHHC-7 and -21 enzymes thereby regulating mERa expression.