Expression of multiple forms of 3 beta-hydroxysteroid dehydrogenase in the mouse liver during fetal and postnatal development.
Expression of multiple forms of 3 beta-hydroxysteroid dehydrogenase in the mouse liver during fetal and postnatal development.
复制标题
胎儿和出生后发育期间小鼠肝脏中多种形式的 3β-羟基类固醇脱氢酶的表达。
DOI：
10.1016/0303-7207(95)03707-1
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发表时间：
1996
影响因子：
4.1
通讯作者：
Payne,AH
中科院分区：
文献类型：
--
作者：
Park,CH;Abbaszade,IG;Payne,AH
酶- 3β-羟基类固醇脱氢酶（3βHSD）是所有类固醇激素的生物合成所必需的。迄今为止，本实验室已在小鼠中分离并鉴定了5种不同的3βHSD cdna （3βHSD I-V）。不同的同工异构体分为两个功能不同的组。3βHSD I和III作为脱氢酶/异构酶，3βHSD IV和V作为3-酮类固醇还原酶。先前研究表明，成年小鼠肝脏表达3βHSD II、III和V，其中3βHSD III是主要亚型。本研究检测了不同形式的3βHSD mrna和蛋白在雄性和雌性小鼠的肝脏在胎儿和出生后发育过程中的表达。在成年小鼠中仅在性腺和肾上腺中表达的3βHSD I是胎儿发育期间雄性和雌性肝脏中表达的主要亚型，直到出生后第一天（pn）之后，3βHSD III成为主要亚型。3βHSD I mRNA和蛋白在20pn后完全停止表达。3βHSD V的表达在第40天首次被检测到，并且仅在雄性中被观察到。在整个发育过程中检测到3βHSD II mRNA的极低表达。先前对表达蛋白酶活性的表征表明，3βHSD I对Δ5-3β-hydroxysteroids的km值低于3βHSD III，这表明3βHSD I是比3βHSD III更有效的3β-羟基类固醇脱氢酶/异构酶。本研究结果提示肝脏可能在小鼠胎儿发育过程中类固醇激素的生物合成中起重要作用。
The enzyme 3β-hydroxysteroid dehydrogenase (3βHSD) is essential for the biosynthesis of all steroid hormones. To date this laboratory has isolated and characterized five distinct 3βHSD cDNAs in the mouse (3βHSD I–V). The different isoforms fall into two functionally distinct groups. 3βHSD I and III function as dehydrogenase/isomerases and 3βHSD IV and V function as 3-ketosteroid reductases. Previously it was shown that the liver of the adult mouse expresses 3βHSD II, III and V, with 3βHSD III being the major isoform. This study examines the expression of the different forms of 3βHSD mRNAs and proteins in the livers of male and female mice during fetal and postnatal development. 3βHSD I, which in the adult mouse is expressed only in the gonads and adrenal glands, is the major isoform expressed in both male and female livers during fetal development until the first postnatal (pn) day after which time 3βHSD III becomes the major isoform. Expression of 3βHSD I mRNA and protein completely ceases after day 20 pn. The expression of 3βHSD V is first detected at day 40 pn and is observed only in the male. Very low expression of 3βHSD II mRNA is detected throughout development. Previous characterization of enzymatic activity of the expressed proteins showed that 3βHSD I exhibits lower Kmvalues for the Δ5-3β-hydroxysteroids than 3βHSD III, indicating that 3βHSD I functions as a more efficient 3β-hydroxysteroid dehydrogenase/isomerase than 3βHSD III. The results of this study suggest that the liver may play an important role in the biosynthesis of steroid hormones during murine fetal development.