Accumulating evidence suggest that membrane progestin receptor α (mPRα) is the membrane receptor mediating nongenomic progestin signaling that induces oocyte maturation in teleost. However, the involvement of other members of mPR family in oocyte maturation is still unclear. In this study, we found impaired oocyte maturation in zebrafish lacking mPRα1, mPRα2, mPRβ, or mPRγ2. In contrast, no difference was observed in oocyte maturation in the single knockout of mPRγ1, mPRδ, or mPRε. To study possible redundant functions of different mPRs in oocyte maturation, we generated a zebrafish line lacking all seven kinds of mPRs (mprs-/-). We found oocyte maturation was further impaired in mprs-/-. In addition, oocyte ovulation delay was observed in mprs-/- females, which was associated with low levels of nuclear progestin receptor (Pgr), a key regulator for ovulation. We also found reduced fertility in mprs-/- female zebrafish. Furthermore, eggs spawned by mprs-/- females were of poor quality.

中文翻译：

---

斑马鱼的膜孕激素受体（mPR）基因敲除的卵母细胞成熟和排卵障碍。

越来越多的证据表明，膜孕激素受体α（mPRα）是介导非基因组孕激素信号传导的膜受体，可诱导硬骨鱼卵母细胞成熟。但是，尚不清楚mPR家族的其他成员是否参与卵母细胞的成熟。在这项研究中，我们发现缺少mPRα1，mPRα2，mPRβ或mPRγ2的斑马鱼的卵母细胞成熟受损。相反，在单敲除mPRγ1，mPRδ或mPRε的卵母细胞成熟中未观察到差异。为了研究卵母细胞成熟过程中不同mPR的可能冗余功能，我们生成了一种缺少所有七种mPR（mprs-/-）的斑马鱼品系。我们发现卵母细胞成熟在mprs-/-中进一步受损。此外，在mprs //女性中观察到卵母细胞排卵延迟，这与核孕激素受体（Pgr）的水平低有关，排卵的关键调节剂。我们还发现mprs-/-雌性斑马鱼的生育力降低。此外，mprs-/-雌性产卵的质量较差。