Qin K N, Cheng K C
Department of Pediatrics, Cornell University Medical College, New York, New York 10021.
Biochemistry. 1994 Mar 22;33(11):3223-8. doi: 10.1021/bi00177a012.
We previously identified multiple proteins structurally related to 3 alpha-hydroxysteroid dehydrogenase in rat liver, lung, kidney, and testis ((1991) Arch. Biochem. Biophys. 291, 258-262). We further used these monoclonal antibodies to screen several lambda gt11 cDNA libraries derived from male rat liver, lung, and kidney. Five additional unique cDNA clones were isolated and sequenced; the proteins encoded by these cDNAs were found to exhibit 37-62% amino acid sequence homology to rat liver 3 alpha-hydroxysteroid dehydrogenase. Because these encoded proteins belong to the aldo-keto reductase superfamily, we named these proteins RAKa to RAKf. RAK represents rat aldo-keto reductase, and RAKa is the previously described rat liver 3 alpha-HSD. Northern blot analysis and reverse transcription-polymerase chain reactions were performed to examine their expression in various tissues. Only RAKe, which resembles human aldehyde reductase, was ubiquitously expressed in liver, kidney, lung, and other tissues, while the remaining mRNAs were found to have a more tissue- and sex-specific distribution. Genomic blot analysis showed complex, yet distinctive, restriction band patterns when different cDNAs were used as probes, suggesting that these cDNA clones are products of different genes and more related gene(s) may exist.
我们之前在大鼠肝脏、肺、肾脏和睾丸中鉴定出多种与3α-羟基类固醇脱氢酶结构相关的蛋白质（(1991)《生物化学与生物物理学报》291, 258 - 262）。我们进一步使用这些单克隆抗体筛选了几个来自雄性大鼠肝脏、肺和肾脏的λgt11 cDNA文库。另外分离并测序了五个独特的cDNA克隆；发现这些cDNA编码的蛋白质与大鼠肝脏3α-羟基类固醇脱氢酶的氨基酸序列同源性为37% - 62%。由于这些编码的蛋白质属于醛糖酮还原酶超家族，我们将这些蛋白质命名为RAKa至RAKf。RAK代表大鼠醛糖酮还原酶，RAKa是先前描述的大鼠肝脏3α-HSD。进行了Northern印迹分析和逆转录-聚合酶链反应以检测它们在各种组织中的表达。只有与人类醛还原酶相似的RAKe在肝脏、肾脏、肺和其他组织中普遍表达，而其余的mRNA具有更具组织和性别特异性的分布。基因组印迹分析表明，当使用不同的cDNA作为探针时，会出现复杂但独特的限制性条带模式，这表明这些cDNA克隆是不同基因的产物，可能还存在更多相关基因。
