Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.1.1.3 (HSD)
 3,464 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

20 alpha-Hydroxysteroid dehydrogenase (20 alpha-HSD, EC 1.1.1.149) catalyses the conversion of progesterone into 20 alpha-dihydroprogesterone (20 alpha-OHP). Previously, we purified the enzyme (37 kDa) from rat ovary and determined its N-terminal amino acid sequence. In the present study we succeeded in cloning a full-length 20 alpha-HSD cDNA. mRNA was extracted from immature rat ovaries after successive treatment with equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG). A cDNA library was constructed in lambda ZAP. For screening, a 576 bp probe was amplified by the PCR using mixed primers based on the N-terminal sequence of 20 alpha-HSD, and labelled with [32P]dCTP. Eight positive clones were isolated from 1.2 x 10(4) recombinants. Analysis of the nucleotide sequence revealed that one clone of 1.2 kbp cDNA (pHSD12-07) contained a polyadenylation site and an open reading frame encoding 323 amino acids with the N-terminal sequence of 20 alpha-HSD. The fusion protein of pHSD12-07 produced by Escherichia coli reacted with a specific polyclonal antibody generated against rat ovarian 20 alpha-HSD. In addition, the in vitro transcription-translation product produced by Xenopus oocytes showed 20 alpha-HSD activity and Northern-blotting analysis revealed that the ovaries from normal adult rats contained a 1.2 kb mRNA. Thus we succeeded in isolating a clone encoding the full length of rat ovarian 20 alpha-HSD. The sequence showed high similarity with those of rat liver 3 alpha-hydroxysteroid dehydrogenase (3 alpha-HSD), bovine lung prostaglandin F synthase (PGFS), human liver chlordecone reductase (CDR), frog lens rho-crystallin and aldose reductases, indicating that 20 alpha-HSD belongs to the aldo-keto reductase family.
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PMID:Molecular cloning of cDNA for rat ovarian 20 alpha-hydroxysteroid dehydrogenase (HSD1). 817 18

Retinal pigment epithelium (RPE) has essential roles that maintain functions of the neural retina. Previously, we described that the 3b5 monoclonal antibody (3b5 mAb) recognized the RPE cells in the chick embryonic eye. In the present study, a gene coding for the 3b5 antigen has been cloned and sequenced. A 10-day-old embryonic RPE cDNA library was constructed in lambda Uni-ZAP XR, and screened with the 3b5 mAb as a probe. The complete nucleotide sequence of the antigen recognized by the 3b5 mAb was obtained. The cDNA encodes a 735 amino acid protein with a calculated molecular mass of 80,147 Da. The deduced amino acid sequence shares 72% identity with the human 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) type IV. Northern blot analysis detected a 2.9 kb transcript. Immunohistochemical and in-situ hybridization studies revealed that 17 beta-HSD type IV was preferentially expressed in the RPE cells. The expression of steroid metabolizing enzymes in the RPE cells is able to create estrogenic environment, which may have a role of maintenance of the neural retina.
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PMID:Expression of 17 beta-hydroxysteroid dehydrogenase type IV in chick retinal pigment epithelium. 924 2