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Query: UNIPROT:P06889 (Mol)
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Using a recently cloned rat ovary 3 beta-HSD cDNA and antibodies raised against purified human placental 3 beta-HSD, we have studied the effects of treatment with human chorionic gonadotropin (hCG) and hyperprolactinemia achieved by pituitary implants, alone or in combination, on the expression and activity of ovarian 3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4 isomerase (3 beta-HSD) in intact adult rats. 32P- and 35S-labeled cDNA probes were used to evaluate the effects of treatments on 3 beta-HSD mRNA levels by dot blot and in situ hybridization, respectively, while enzymatic activity was measured by the conversion of [14C]dehydroepiandrosterone into [14C]androstenedione. The present data show that hCG exerts a marked trophic effect on rat corpora lutea with an increase in total ovarian 3 beta-HSD mRNA levels, 3 beta-HSD protein content as well as enzymatic activity, resulting in an increase in serum progesterone levels. Prolactin-secreting pituitary implants alone, on the other hand, while exerting small effects on 3 beta-HSD expression and activity, led to a marked potentiation of the stimulatory effect of hCG on all parameters. The present data show that hCG and PRL act synergistically to stimulate ovarian progesterone secretion via an increase in 3 beta-HSD mRNA levels, protein content and enzymatic activity.
Mol Cell Endocrinol 1990 Aug 20
PMID:Effects of human chorionic gonadotropin (hCG) and prolactin (PRL) on 3 beta-hydroxy-5-ene-steroid dehydrogenase/delta 5-delta 4 isomerase (3 beta-HSD) expression and activity in the rat ovary. 214 42

The present studies examined responses to hCG and/or insulin of 3 beta-hydroxy-5-ene-steroid dehydrogenase and steroid 5----4-ene-isomerase activity (3 beta-HSD) in cultured Band 2 and Band 3 cells from 25- to 40-day-old rats isolated on Percoll gradients. In Band 2 cells, from 25-day-old rats enzyme activity increased about 3- and 2.5-fold, after 6 days of exposure to hCG or insulin, respectively. However, hCG did not stimulate enzyme activity in Band 2 cells from 30-, 35- and 40-day-old animals, and responses to insulin alone or insulin plus hCG declined with age. In Band 3 cells only insulin increased enzyme activity at each age. Neither hCG or insulin altered DNA levels in Band 2 or Band 3 cells, suggesting that increased activity in Band 2 cells from 25-day-old rats was not due to cellular replication. However, hCG increased the number of cells staining positive for 3 beta-HSD about 4-fold in Band 2 cells from 25-day-old rats. Insulin did not increase the number of positive staining cells in Band 2 and Band 3 cells from 25-day-old rats, suggesting that its major effect was to increase enzyme activity in existing cells. These results suggest that during a limited period of maturation precursor cells in Band 2, which are undetected by histochemical staining for 3 beta-HSD, can be converted to Leydig cells in culture by hCG.
J Steroid Biochem Mol Biol 1990 Dec 10
PMID:Evidence that Leydig precursors localize in immature band two cells isolated on Percoll gradients. 217 28

Human placental 3 beta-hydroxysteroid dehydrogenase/5----4-ene isomerase (3 beta-HSD) purified from human placenta transforms C-21 (pregnenolone and 17 alpha-hydroxy pregnenolone) as well as C-19 (dehydroepiandrosterone and androst-5-ene-3 beta, 17 beta-diol) steroids into the corresponding 3-keto-4-ene-steroids and is thus involved in the biosynthesis of all classes of hormonal steroids. Trilostane, epostane and cyanoketone are potent inhibitors of 3 beta-HSD with Ki values of approximately 50 nM. 4-MA, a well known 5 alpha-reductase inhibitor, is also a potent inhibitor of 3 beta-HSD with a Ki value of 56 nM. Synthetic progestin compounds such as promegestone and RU2323 show relatively strong inhibitory effects with Ki values of 110 and 190 nM, respectively. Cyproterone acetate, a progestin used in the treatment of hirsutism, acne and prostate cancer as well as norgestrel and norethindrone that are widely used as oral contraceptives also inhibit 3 beta-HSD activity at Ki values of 1.5, 1.7 and 2.5 microM, respectively.
J Steroid Biochem Mol Biol 1990 Oct
PMID:Inhibitory effect of synthetic progestins, 4-MA and cyanoketone on human placental 3 beta-hydroxysteroid dehydrogenase/5----4-ene-isomerase activity. 226 54

3 alpha, 20 beta-Hydroxysteroid dehydrogenase, an NADH-dependent oxidoreductase isolated from Streptomyces hydrogenans , is a tetramer containing four subunits each of Mr 25,000. The enzyme has been crystallized by the vapor diffusion technique using either phosphate or borate buffered ammonium sulfate (pH between 6.0 and 8.7) as the precipitant. The crystals are hexagonal bipyramids ; they have the symmetry of space group P6(4)22 (or P6(2)22), with unit cell dimensions a = 127.3 A, c = 112.2 A. Volume and density considerations imply that the crystallographic asymmetric unit contains two monomers, and therefore that the tetramer possesses a 2-fold axis of symmetry that is coincident with a crystallographic 2-fold symmetry element.
J Mol Biol 1984 May 15
PMID:Crystallization and preliminary crystallographic study of 3 alpha, 20 beta-hydroxysteroid dehydrogenase from Streptomyces hydrogenans. 658 18

Recent results from a number of laboratories have led us to re-examine the role of 3 beta-androstanediol in the rat ventral prostate. Whereas previously 5 alpha-dihydrotestosterone and 3-beta androstanediol were thought to have distinctly separate effects on the prostate, we suggest that 3 beta-androstanediol serves only as an intermediate in the metabolism and removal of 5 alpha-dihydrotestosterone from the organ. In our view the action of androgens on the prostate are exerted exclusively through the binding of 5 alpha-dihydrotestosterone to the androgen receptor and its subsequent translocation to the nucleus. Differences in effects are related to the amount of 5 alpha-dihydrotestosterone available to the gland. 3 alpha-Hydroxysteroid dehydrogenase may play a critical role in modulating the level of 5 alpha-dihydrotestosterone available to the translocatable receptor.
Mol Cell Endocrinol 1982 Jun
PMID:The role of androgen metabolism in the control of androgen action in the rat prostate. 704 89

11 beta-Hydroxysteroid dehydrogenase (11 beta-HSD) is a microsomal enzyme complex responsible for the interconversion of active 11-hydroxy glucocorticoids to inactive 11-oxo metabolites. It has long been controversially discussed whether 11-dehydrogenation and 11-oxoreduction are catalysed by a single bidirectional enzyme or if the 11 beta-HSD system comprises 2 kinetically distinct microsomal enzyme activities, 11-dehydrogenase and 11-oxoreductase. However, 11-oxoreduction of homogeneously purified 11 beta-HSD could not be demonstrated under in vitro conditions until today. We have purified 11 beta-HSD from mouse liver microsomes to homogeneity by a purification method which affords a gentle membrane protein solubilization as well as providing a favourable detergent surrounding during the various chromatographic steps. Following 11-dehydrogenation of corticosterone and 11-oxoreduction of dehydrocorticosterone simultaneously throughout the entire purification procedure we could demonstrate that 11 beta-HSD retains both oxidative and reductive activities in almost the same ratio, which is also true for the homogeneously purified enzyme. Deducing from the coincidentally increasing specific activities of 11-dehydrogenation and 11-oxoreduction the conclusion can be drawn that both activities reside within the same protein. Furthermore, in addition to NADP(H) also NAD(H) can serve as cosubstrate, which is mainly true for the oxidative direction. In conclusion, our results provide evidence that the oxidative and reductive behaviour of 11 beta-HSD can be explained by the concept of a unique, reversible oxidoreductase thus disproving the two enzyme theory.
J Steroid Biochem Mol Biol 1994 Feb
PMID:The purification of 11 beta-hydroxysteroid dehydrogenase from mouse liver microsomes. 751 8

A new monoclonal antibody (FDO26G) is described which was raised against purified human 3 beta-hydroxysteroid dehydrogenase type I (3 beta-HSD type I). FDO26G reacted strongly with villous syncytiotrophoblast, weakly with some trophoblast cells in chorion laeve, and not at all with extravillous trophoblast in cytotrophoblast cell islands and decidual trophoblast. All these types of trophoblast reacted strongly with monoclonal antibody FDO161G, which has previously been shown to react with 3 beta-HSD type I and, like FDO26G, reacts strongly with adrenal cells. Mapping experiments using a combination of lacZ fusion polypeptides and synthetic peptides located the FDO26G epitope to residues 354-366 at the C-terminal end of the molecule, a sequence that is identical in the type I and type II forms of the enzyme. The epitope contains a consensus for a casein kinase-II site with serine 359 as the candidate phosphorylation site. This suggested that the lack of reactivity of FDO26G to 3 beta-HSD in extravillous trophoblast might be due to phosphorylation at serine 359. Peptide 354-366 was synthesized with phosphoserine at residue 359 and its binding to FDO26G was compared with that of the unphosphorylated peptide. FDO26G bound the phosphopeptide at least as strongly as the unphosphorylated peptide. It is concluded that the lack of staining of extravillous trophoblast by FDO26G is due to the presence of a different sequence at residues 354-366 and that a hitherto unidentified third isoform of human 3 beta-HSD is expressed in these cells.
J Mol Endocrinol 1994 Jun
PMID:Epitopic heterogeneity of human 3 beta-hydroxysteroid dehydrogenase in villous and extravillous human trophoblast. 752 59

11 beta-Hydroxysteroid dehydrogenase (11 beta-HSD), responsible for the interconversion of hormonally active cortisol to inactive cortisone, dictates specificity for the mineralocorticoid receptor (MR) in the distal nephron and colon. Two isoforms of human 11 beta-HSD have been cloned, an NADP(H)-dependent (type 1) dehydrogenase/oxo-reductase enzyme, and a high-affinity NAD-dependent (type 2) unidirectional dehydrogenase. Using the reverse-transcriptase polymerase chain reaction (RT-PCR) amplification of RNA extracted from human adult tissues, type 1 11 beta-HSD mRNA was found in decidua, placenta, liver, lung, spleen, kidney medulla, cerebellum and pituitary, but was absent in kidney cortex, sigmoid and rectal colon, salivary gland and thyroid. In contrast, type 2 11 beta-HSD mRNA was found only in placenta and in the classical mineralocorticoid target tissues, kidney cortex, kidney medulla, sigmoid and rectal colon, salivary gland, and colonic epithelial cell lines (AAC1 and RGC28). In situ hybridization studies of renal cortex, cortico-medullary junction and medulla using a 35S-labeled antisense cRNA probe for type 2 human 11 beta-HSD, revealed specific localization of type 2 11 beta-HSD mRNA expression exclusively to renal cortical and medullary collecting ducts. Type 1 and type 2 isoforms of human 11 beta-HSD are expressed in a distinct tissue-specific fashion, in keeping with the proposed differences in their physiological roles. Type 2 11 beta-HSD is found predominantly in mineralocorticoid target tissues where it serves to protect the MR in an autocrine fashion.
Mol Cell Endocrinol 1995 Apr 28
PMID:Detection of human 11 beta-hydroxysteroid dehydrogenase isoforms using reverse-transcriptase-polymerase chain reaction and localization of the type 2 isoform to renal collecting ducts. 754 19

Several bands of hydridization are detected when southern blots of human genomic DNA are proved with cDNA of 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) type I. Two experimental approaches were adopted to estimate the size of the 3 beta-HSD gene family. Firstly, primer designed to amplify 3 beta-HSD type I and II genes were found on occasion to amplify DNA products of appropriate length but which were resolved as distinct sequences by denaturing gradient gel electrophoresis (DGGE). Five of these novel bands were cloned and their sequences were found to be closely related to 3 beta-HSD types I and II. Secondly, 57 genomic clones were selected from two lambda genomic libraries by hybridization with exonic probes of 3 beta -HSD type I. These were screened for novel members of the gene family by pcr amplification using various combinations of PCR primers to the type I and II genes, particularly those primers that previously amplified novel PCR products from genomic DNA. Amplification products from (lambda) clones were screened for novel sequences by DGGE. As a result of these approaches, at least five new members of the 3 beta-HSD gene family were found, one of which locates to the 3 beta -HSD type I and II gene cluster on 1p13. The existence of additional closely related but distinct members of the gene family should be recognized as a potential complication when screening PCR fragments for mutations in the type I and II genes. DGGE was found to be an exceedingly rapid means of screening amplification products from (lambda) clones to search for novel members of the gene family.
Mol Cell Probes 1995 Apr
PMID:New members of the 3 beta-hydroxysteroid dehydrogenase gene family. 760 71

Expression of the Cyp 2d-9 (steroid 16 alpha-hydroxylase) gene in mouse liver is male specific in such Mus musculus domesticus strains as FVB/N, whereas the corresponding P450 genes in the wild mouse species Mus spretus are not sex specific in their expression. These parental differences in the gene expressions were independently inherited in F1 offspring from crosses of FVB/N and M. spretus. A 5' flanking sequence (-110CTC CTCCCTATTCCGGGCC-92) was defined as a regulatory element (named SDI-A1) for the domestic Cyp 2d-9 promoter. The nucleotide which corresponds to T at position -99 within SDI-A1 was found to be substituted with C in the wild mouse P450 genes. The placing of C at position -99 abolished the transcriptional activity of SDI-A1 in HepG2 cells as well as the binding of SDI-A1 to a nuclear factor. This factor (designated NF2d9) was purified from mouse nuclear extracts, and its cDNA cloned. The purified NF2d9 bound to SDI-A1 but not to the mutated SDI-A1 with C at position -99. The deduced amino acid sequence revealed that NF2d9 is 72 and 94% identical to mouse CP2 and human LBP-1a, respectively. NF2d9 thus belongs to the CP2 family and is the mouse homolog of human LBP-1a, which modulates human immunodeficiency virus type 1 transcription. Anti-NF2d9, which was raised against the bacterially expressed protein, supershifted the SDI-A1 complex with the liver nuclear extract. Both the bacterially expressed and in vitro-translated NF2d9 inhibited SDI-A1 complex formation, although they did not bind to SDI-A1 directly. The results, therefore, indicate that the domestic Cyp 2d-9 gene can be regulated through a specific association of NF2d9 with SDI-A1.
Mol Cell Biol 1995 Aug
PMID:A nuclear factor (NF2d9) that binds to the male-specific P450 (Cyp 2d-9) gene in mouse liver. 762 10


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