Ogura K, Kajita J, Narihata H, Watabe T, Ozawa S, Nagata K, Yamazoe Y, Kato R
Department of Hygienic Chemistry, Tokyo College of Pharmacy, Japan.
Biochem Biophys Res Commun. 1989 Nov 30;165(1):168-74. doi: 10.1016/0006-291x(89)91050-4.
Nothing has been known of the cDNAs encoding sulfotransferases (STs) that catalyze sulfation of steroids and xenobiotics. In the present study, a female Sprague-Dawley (SD) rat liver cDNA library was screened with rabbit anti-serum raised against hydroxysteroid ST a (STa) purified from female SD rat liver cytosol. The cDNA isolated from the library consisted of 1,028 base pairs which had an open reading frame of 852 base pairs encoding the entire rat ST subunit of 284 amino acids. The N-terminal amino acid sequences of STa and the rat liver hydroxysteroid ST, bile acid ST I, both elucidated previously by the chemical method, had a strong homology with that deduced from the cDNA. Northern blot analysis of total RNAs from female and male rat livers showed a marked sex difference (female much greater than male) in the expressed level of the mRNA for the predicted ST subunit protein. A remarkable sex difference (female much greater than male) was also observed by immuno-blot analysis in the level of the hydroxysteroid ST protein(s) cross-reacting with the anti-serum in the rat liver cytosols.
关于编码催化类固醇和外源性物质硫酸化的磺基转移酶（STs）的cDNA，此前一无所知。在本研究中，用针对从雌性SD大鼠肝脏胞质溶胶中纯化的羟基类固醇STa（STa）制备的兔抗血清，筛选雌性Sprague-Dawley（SD）大鼠肝脏cDNA文库。从文库中分离出的cDNA由1028个碱基对组成，其开放阅读框为852个碱基对，编码由284个氨基酸组成的完整大鼠ST亚基。此前通过化学方法阐明的STa和大鼠肝脏羟基类固醇ST、胆汁酸ST I的N端氨基酸序列，与从cDNA推导的序列具有很强的同源性。对雌性和雄性大鼠肝脏总RNA的Northern印迹分析表明，预测的ST亚基蛋白的mRNA表达水平存在明显的性别差异（雌性远高于雄性）。在大鼠肝脏胞质溶胶中，通过免疫印迹分析也观察到与抗血清发生交叉反应的羟基类固醇ST蛋白水平存在显著的性别差异（雌性远高于雄性）。
