鯉魚性腺刺激素β次單元基因之雌性素 responsive element 結合因數定性研究

Abstract

利用gel retardation assay，我們發現鯉魚腦下腺細胞核萃取液含有一核蛋白，可以高度專一性地與鯉魚性腺刺激素β次單元基因5'端之estrogen responsive element(ERE)結合。根據South-Western blotting assay之結果得知其分子量約為67kDa。此外，以分子篩管柱自鯉魚腦下腺細胞核萃取液純化分子量為67kDa的雌性素受體(Estrogen receptor)亦可與ERE高度專一性地結合。因此，鯉魚腦下腺細胞核內可與ERE結合之核蛋白可能即是雌性素受體。當其與E2結合後，可與ERE結合進而調控性腺刺激素β次單元基因之表現。

Using gel retardation assay, a pituitary nuclear factor which can bind with high sequence specificity to the putative estrogen responsive element (ERE) in the 5'-promoter region of carp gonadotropin (GTH) β subunit gene was identified. Its molecular weight was determined to be 67 kDa by South-Western blotting assay. The 67 kDa estrogen receptor partially purified from pituitary nuclear extract by gel filtration also showed highly specific binding to the putative ERE in the filter binding assay. These data suggest that the nuclear factor be estrogen receptor which, when associated with estradiol, can bind to the ERE of carp GTE β subunit gene and then regulate its expression as in higher vertebrates.