小白鼠子宮分泌液純化出的24P3蛋白質之生化研究

Abstract

藉著G100色層分析的管柱，從未成熟的老鼠子宮分泌，純化出一個動情激素誘導的蛋白質，此蛋白質由SDS-PAGE 估算出分子量約為 2 6KDa ，進一步分析得知，此類蛋白質為醣蛋白，主蛋白的等電點為 5.8 ，次要蛋白的等電點為 6.7 ，蛋白質部份的分子量估計為 2 3KDa，它的N-端的胺基酸被阻斷。藉由CNBr 切除所得之部分胺基酸序列證明其為 24P3 基因產物。由免疫組織化學分佈得知，此蛋白質是由動情激素誘導並主要分佈於子宮之 glandular 與 luminal epithelial細胞。

An estrogen-induced secretory protein from mouse uterine luminal fluid was purified by Sephadex G-l00 Chromatography. This protein has an apparent molecular mass of approx 26KDa as determined by SDS-PAGE. The purified protein revealed that a major component with isoelectric point at 5.8 and a minor component with isoelectric point at 6.7. Deglycosylation of the protein gave the 23KDa protein core. The N-terminus of this protein appeared to be blocked. The partial amino acid sequence of a peptide fragment obtained by CNBr cleavage of the protein was identified to TLYGRIKELS. The sequence is identical to that deduced from 24P3 gene. Results of western blotting analysis revealed the presence of 24P3 gene protein in non-sexual organ such as lung, spleen, and in female sexual organ like uterus and vagina. Steroid hormone regulation of 24P3 gene protein was examined in uterus of adult female mice. The ovariectomized mice show no 24P3 gene protein in the uterus, but the protein appears when the animal were given a single injection of estrogen after castration for 7 days. Immunocytochemical localization showed that 24P3 gene protein was highly abundant in glandular and luminal epithelial cells of Uterus.