Purpose: To determine expression of G-protein estrogen receptor (GPER) in mouse oocyte membrane during maturation.
Methods: The expression of GPER from different maturation stages of oocytes, in vivo and in vitro matured oocytes as well as aging oocytes was examined by immune-fluorescence GPR30 antibody and the images were analyzed by laser scanning confocal microscope. Further confirmation was performed by Western blots for cell fractionation.
Results: Significant fluorescent signal was observed on the surface of mouse oocytes. The image expression was lower in germinal vesicle (GV) stage than mature metaphase-II (M-II) stage oocytes. There was high expression in in-vivo matured oocytes compared to in vitro matured oocytes. The highest expression was observed in aging oocytes compared with other oocytes.
Conclusions: The changes of expression of GPER on mouse oocytes plasma membrane confirm oocyte membrane maturation, suggesting that those changes of GPER may be related to the functional role of oocyte maturation.