雌激素主要通过雌激素受体发挥其生物学功能。雌激素受体属于转录因子核受体家族。ER-α36是最近发现的一个雌激素受体α的变异体,它在雌性生殖器官的表达和作用还不清楚。
本研究采用激光共聚焦显微术、蛋白免疫印记和抗体注射等方法分别研究了ER-α36的在小鼠卵巢发育及卵母细胞减数分裂过程中的表达、亚细胞定位,以及它在小鼠卵母细胞减数分裂过程中的可能作用。ER-α36表达在各发育阶段的卵泡卵母细胞核内,直到卵母细胞恢复减数分裂为止(GVBD)。它在颗粒细胞上有少量表达,但在颗粒细胞向黄体细胞转化时,它的表达量上升,且主要分布于黄体细胞的胞质,细胞核上有很少或没有表达。此外,ER-α36还表达在卵泡膜细胞(theca cells)上。与对照组相比,用ER-α36抗体注射到卵母细胞生发泡中来封闭ER-α36的功能,可使第一极体提前排出。这些结果表明ER-α36可能在小鼠卵巢卵泡发生和卵母细胞减数分裂中起重要的作用。本研究发表在《组织化学和细胞生物学》(HISTOCHEMISTRY AND CELL BIOLOGY)杂志上。(生物谷Bioon.com)
生物谷推荐原始出处:
HISTOCHEMISTRY AND CELL BIOLOGY,doi: 10.1007/s00418-008-0526-4,Bao-Zeng Xu,Qing-Yuan Sun
Changes in estrogen receptor-α variant (ER-α36) expression during mouse ovary development and oocyte meiotic maturation
Bao-Zeng Xu1, 2, Sheng-Li Lin1, 2, Mo Li1, 2, Jia-Qiao Zhu1, 2, Sen Li1, 2, Ying-Chun Ouyang1, Da-Yuan Chen1 and Qing-Yuan Sun1
(1) State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Datun Road, Chaoyang, 100101 Beijing, China
(2) Graduate School, Chinese Academy of Sciences, Beijing, China
Abstract The biological effects of estrogens are largely mediated through estrogen receptors (ERs), which belong to the nuclear receptor gene family of transcription factors. ER-α36 has been recently identified as a new variant of ERα, but its expression and roles in female reproduction system remain unknown. Immunocytochemistry and confocal microscopy were employed to observe ER-α36 distribution in mouse ovary during postnatal development and in oocyte during meiotic maturation. ER-α36 was consistently present in the nuclei of oocytes regardless of follicular growth stage and mouse age until germinal vesicle breakdown (GVBD). Its immunosignal was smeared in granulosa cells. However, the ER-α36 signal is up-regulated and found in cytoplasm with little or no nuclear staining during corpus luteum development. ER-α36 was also found in theca cells. We showed by Western blot that ER-α36 was expressed in mouse oocytes at various maturation stages. When the function of nuclear ER-α36 was blocked by microinjecting anti-ER-α36 specific antibody into the germinal vesicle (GV) of mouse oocytes, the first polar body emission occurred earlier in a higher proportion of oocytes compared to the control. These results suggest that ER-α36 may play critical roles in mouse ovarian folliculogenesis and oocyte development.