Hanna Richard N, Zhu Yong
Department of Biology, Howell Science Complex, East Carolina University, 1000 E, 5th Street, Greenville, NC 27858-4553, USA.
Gen Comp Endocrinol. 2009 Mar;161(1):153-7. doi: 10.1016/j.ygcen.2008.10.006. Epub 2008 Oct 12.
A distinct family of membrane progestin receptors (mPRalpha, mPRbeta, and mPRgamma) that mediate rapid, nongenomic actions of progestins has been identified and characterized in several fish species as well as in frogs, rats, pigs, and humans. However, few studies to date have thoroughly examined tissue specific expression of mPR protein and transcripts in any model species. In the present study, the expression of both mPRalpha and mPRbeta in zebrafish was examined by RT-PCR, Western blotting and immunohistochemistry using mPR specific primers and antibodies. The proteins and mRNAs of mPRalpha and mPRbeta were co-localized in the major reproductive organs, including the ovary, testis, and pituitary. Both mPRalpha and mPRbeta were found in scattered cells in the pituitary for the first time. In the testis, immunostaining of mPRalpha was restricted to the sperm, while mPRbeta was found in spermatocytes and spermatogonia. In the ovary, both mPRalpha and mPRbeta were detected in denude oocytes and follicular layer cells. Furthermore, mPRalpha and mPRbeta proteins were localized at or near the oocyte membrane of maturationally competent stage IV oocytes in a probable location for mediating progestin-induced nongenomic signaling in oocytes.
一种独特的膜孕激素受体家族（mPRα、mPRβ和mPRγ）已在几种鱼类以及青蛙、大鼠、猪和人类中被鉴定和表征，它们介导孕激素的快速非基因组作用。然而，迄今为止，很少有研究在任何模式物种中彻底检查mPR蛋白和转录本的组织特异性表达。在本研究中，使用mPR特异性引物和抗体，通过RT-PCR、蛋白质印迹和免疫组织化学检测了斑马鱼中mPRα和mPRβ的表达。mPRα和mPRβ的蛋白质和mRNA共定位于主要生殖器官，包括卵巢、睾丸和垂体。首次在垂体的散在细胞中发现了mPRα和mPRβ。在睾丸中，mPRα的免疫染色仅限于精子，而mPRβ存在于精母细胞和精原细胞中。在卵巢中，在裸卵母细胞和卵泡层细胞中检测到了mPRα和mPRβ。此外，mPRα和mPRβ蛋白定位于成熟的IV期卵母细胞的卵母细胞膜处或附近，这可能是介导孕激素诱导的卵母细胞非基因组信号传导的位置。
