内质网蛋白27(ERp27)在小鼠卵母细胞的定位及在精卵融合中的作用

Localization of ERp27 on mouse oocytes and its role in gamete fusion

目的探讨内质网蛋白27(ERp27)在小鼠卵母细胞的表达定位,以及该蛋白在小鼠精卵融合中的作用。方法将性成熟后的小鼠促排卵后,取出卵母细胞,并分为空白对照组(不做任何处理)、阴性对照组(与正常血清IgG共孵育)、抗ERp27抗体封闭组(与抗ERp27单克隆抗体共孵育),用免疫荧光法检测ERp27在小鼠卵母细胞上的定位;通过穿卵实验观察抗ERp27抗体对受精率、受精指数的影响。结果免疫荧光结果显示ERp27在小鼠MI期卵母细胞主要分布在胞浆的周边区域中,在MⅡ期卵母细胞则均匀分布于卵母细胞胞质;穿卵实验结果显示,空白对照组、阴性对照组及抗ERp27抗体封闭组受精率分别为90.91%、89.13%和76.00%,差异无统计学意义(P>0.05),受精指数分别为(5.20±1.32)、(5.40±1.07)和(3.20±0.92),抗ERp27抗体封闭组的受精指数显著低于空白对照组和阴性对照组,差异有统计学意义(P<0.05)。结论 ERp27在小鼠MⅠ及MⅡ期卵母细胞中均有表达,该蛋白可能与精卵融合有关。

Objective： To investigate the localization of endoplasmic reticulum protein 27 （ERp27） on mouse oocytes and its role in gamete fusion. Methods： The oocytes were collected from sexually mature male mice after controlled ovarian hyperstimulation. The oocytes were randomly divided into blank control （no treatment） group,negative control （co-incubated with IgG） group and anti-ERp27 group （co-incubated with ERp27 antibody）. The localization of ERp27 was detected by immunofluorescence analysis. The effect of anti-ERp27 antibody on fertilization rate （FR） and fertilization index （FI） was observed by sperm-oocyte fusion assay. Results： According to indirect immunofluorescence analysis, ERp27 was mainly distributed in the cytoplasm of the peripheral region in M I oocytes, while evenly distributed in the cytoplasm in M II oocytes. The fertilization rate （90.91% vs. 89.13% vs. 76.00%） was not significantly different among the blank control, negative control and anti ERp27 groups （P〉0.05）. The fertilization index of anti ERp27 group （3. 20± 0. 92） was significantly lower than the other two groups [（5. 20±1. 32） , （5. 40±1.07） ]（P〈0. 05）. Conclusions： ERp27 was expressed in MI and M Ⅱ stage oocytes in mouse and this protein may play a role in facilitating sperm-oocyte fusion.