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Query: UNIPROT:P06889 (
Mol
)
630,302
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The structural gene encoding human 3 beta-hydroxysteroid dehydrogenase/delta 5----4-isomerase (3 beta
HSD
) was isolated from a human EMBL3 genomic library. The gene encompasses approximately 8 kilobases of DNA and is comprised of two large introns and three exons encoding amino acid residues 1-48, 49-103, and 104-373, respectively. The exonic sequence is identical to that of the cDNA that we previously isolated and expressed in COS 1 cells. DNA sequence analysis reveals a putative TATA (TATATAA) motif 26 basepairs up-stream of the beginning of exon I, as determined by S1 nuclease protection analysis. However, primer extension analysis using poly(A)+ RNA isolated from both placenta and corpora lutea indicates that the RNA initiates up-stream of the putative TATA motif, and that an additional 53-basepair exon, which is untranslated, is present 5' to the first coding exon. Southern hybridization analysis of genomic DNA using a single exon probe suggests that there may be more than one copy of the gene in the human genome. In addition, we confirm from Southern analysis of genomic DNA isolated from human x hamster somatic cell hybrids that the gene is located on human chromosome 1. These findings will provide a foundation for the characterization of apparent 3 beta
HSD
clinical deficiencies when these are due to a mutation in the structural gene.
Mol
Endocrinol 1990 Dec
PMID:Structural analysis of the gene encoding human 3 beta-hydroxysteroid dehydrogenase/delta 5----4-isomerase. 208 86
Progesterone has been shown to decrease occupied pituitary and uterine nuclear estradiol receptor (E2R) binding in mature and immature estrogen-primed rats. Progesterone has also been shown to stimulate pituitary but not uterine 17 beta-hydroxysteroid dehydrogenase (17 beta-
HSD
) in the rat. The conversion of estradiol to its less active metabolite estrone by 17 beta-
HSD
and activation of phosphatase are among mechanisms considered to be involved in the reduction of E2R. To determine if 17 beta-
HSD
stimulation was a mechanism by which progesterone induced nuclear E2R decrease, the synthetic estrogen ethinylestradiol, which is not oxidized by 17 beta-
HSD
, was used instead of estradiol to prime adult ovariectomized rats. When ethinylestradiol-primed rats received 0.8, 2.0 or 4.0 mg/kg body wt of progesterone 2 h before sacrifice, the total and occupied nuclear E2R accumulation in the anterior pituitary by a subsequent ethinylestradiol injection 1 h later did not show any decrease. This response was different from that observed previously in estradiol-primed animals in which progesterone showed a multiphasic decrease of occupied form of nuclear E2R. However, in the uterus of ethinylestradiol-primed rats, a partial decrease of total and occupied nuclear E2R accumulation was observed in the presence of the three doses of progesterone used. The decrease of uterine nuclear E2R with the three progesterone doses was different from the dose-dependent effect of progesterone observed in the uterus of estradiol-primed rats. Affinity constants of the interaction between [3H]estradiol and the nuclear E2R were similar among groups treated with ethinylestradiol, estradiol and progesterone. These results demonstrate the involvement of 17 beta-
HSD
in the reduction of anterior pituitary gland E2R by progesterone in the estradiol-treated animals. Furthermore, the mechanism of decrease of E2R by progesterone in the uterus appears to be different from the pituitary gland.
J Steroid Biochem
Mol
Biol 1990 Sep
PMID:Role of 17 beta-hydroxysteroid dehydrogenase in the modulation of nuclear estradiol receptor binding by progesterone in the rat anterior pituitary gland and the uterus. 217 25
We studied the effect of the tumor-promoting phorbol ester phorbol 12-myristate 13-acetate (PMA), which activates protein kinase-C, on porcine granulosa cells in culture. PMA as well as cholera toxin, forskolin, and hCG increased cAMP accumulation. PMA further augmented the elevation in cAMP accumulation induced by cholera toxin, forskolin, and hCG. In the same cell culture model, hCG induced a time-dependent increase in the 3 beta-hydroxy-5-ene steroid dehydrogenase (3 beta
HSD
) mRNA levels with a maximal 3-fold stimulation obtained at 8-16 h of incubation with 1 IU hCG/ml. PMA inhibited the increase in 3 beta
HSD
mRNA levels induced by hCG in a dose-dependent manner. The phorbol ester also inhibited the increase in 3 beta
HSD
mRNA levels stimulated by LH as well as cholera toxin and forskolin and the cAMP analogs (Bu)2cAMP and 8-bromo-cAMP. Activation of protein kinase-C by mezerein similarly inhibited hCG stimulation of 3 beta
HSD
mRNA levels. The present data indicate that activation of the protein kinase-C pathway induces generation of cAMP, but causes a near-complete inhibition of the stimulatory effects of hCG, LH, forskolin, cholera toxin, and cAMP analogs on 3 beta
HSD
mRNA levels in porcine granulosa cells in culture.
Mol
Endocrinol 1990 Oct
PMID:Regulation of mRNA expression of 3 beta-hydroxy-5-ene steroid dehydrogenase in porcine granulosa cells in culture: a role for the protein kinase-C pathway. 217 18
Previous studies have demonstrated that progesterone is the primary product of steroidogenesis in avian granulosa cells during short-term incubation. However, during more prolonged culture, lasting several days, the progesterone content in the medium was found to decrease progressively, indicating in vitro metabolic conversion. In the present study we have isolated and identified a number of progesterone metabolites. Granulosa cells, isolated from mature ovarian follicles of laying hens, were cultured in medium 199 supplemented with fetal calf serum and containing [14C]progesterone. After 4 days in culture, cells + media were extracted and the radioactive metabolites separated and identified by TLC, HPLC and GC-MS. Several of the metabolites were further characterized by derivatization and crystallization to constant specific activity. A total of 24 radioactive substances was detected. Of these, 15 have been positively identified, 5 tentatively and the remaining 4 are unidentified. The principal metabolite, representing more than 45% of the total radioactivity, was identified as 3 alpha-hydroxy-5 beta-pregnan-20-one. In addition, significant amounts of 3 alpha-hydroxy-5 alpha-pregnan-20-one (5.76%), 5 beta-pregnane-3,20-dione (3.05%), and 5 alpha-pregnane-3,20-dione (2.95%) were detected and identified. The results indicate that avian granulosa cells possess 3 alpha-hydroxy-steroid dehydrogenase (3 alpha-
HSD
), 17 beta-
HSD
, 20 alpha-
HSD
, 20 beta-
HSD
, 17 alpha-hydroxylase, C17-20-lyase and 5 alpha- and 5 beta-reductase activities. These enzyme activities may convert progesterone to biologically inactive or less active metabolites. However, a functional role for some of these metabolites cannot be ruled out.
J Steroid Biochem
Mol
Biol 1990 Sep
PMID:Metabolism of progesterone by avian granulosa cells in culture. 224 44
Both adipose and epithelial cells isolated from the mammary glands of pregnant and lactating rats show 11 beta-hydroxysteroid dehydrogenase (11-HSD) activity, as measured by conversion of corticosterone to 11-dehydrocorticosterone. Activity in adipose cells from pregnant rats is 3-fold higher than in lactating rats. Epithelial cells from pregnant rats show one-twentieth of the activity of adipose cells, and activity is lower still in epithelial cells from lactating rats. Explants incubated for 48 h extensively metabolized corticosterone to 11-dehydrocorticosterone, and to a much lesser extent to a second unknown metabolite which is found in tissue extracts but not conditioned medium. Mammary gland 11-
HSD
may thus constitute one of the physiological mechanisms preventing premature milk production in response to glucocorticoids.
J Steroid Biochem
Mol
Biol 1990 Nov 30
PMID:Epithelial and adipose cells isolated from mammary glands of pregnant and lactating rats differ in 11 beta-hydroxysteroid dehydrogenase activity. 227 36
Cortisol production from cholesterol requires the activity of four steroid hydroxylases: cholesterol side chain cleavage cytochrome P-450 (P-450scc), 17 alpha-hydroxylase cytochrome P-450 (P-45017 alpha), 21-hydroxylase cytochrome P-450 (P-450C21) and 11 beta-hydroxylase cytochrome P-450 (P-45011 beta). We have previously shown that transformed, nonsteroidogenic COS 1 cells derived from monkey kidney are a useful system for expression of various forms of cytochrome P-450. The present study shows that COS 1 cell cultures multiply transfected with six plasmids containing all four steroid hydroxylases, 3 beta-hydroxysteroid dehydrogenase/delta 5----4-isomerase (3 beta
HSD
) and adrenodoxin produce cortisol and aldosterone when 22(R)-hydroxycholesterol is supplied to the system. When pregnenolone is used as substrate, various intermediate metabolites are detected at different time points further establishing the incorporation of complete functional steroidogenic pathways into the nonsteroidogenic cell cultures. Since the first and the last reactions in these pathways take place in the mitochondrion, the movement of various intermediate metabolites from mitochondrion to endoplasmic reticulum and back to mitochondrion occurs in and between COS 1 cells.
Mol
Cell Endocrinol 1990 Oct 01
PMID:Incorporation of steroidogenic pathways which produce cortisol and aldosterone from cholesterol into nonsteroidogenic cells. 229 41
Two human 17 beta-hydroxysteroid dehydrogenase (17 beta-
HSD
) genes (h17 beta-HSDI and h17 beta-HSDII) included in tandem within an approximately 13 kilobase pair fragment were isolated from a genomic lambda EMBL3 DNA library using cDNA encoding human 17 beta-
HSD
(hpE2DH216) as probe. We have determined the complete exon and intron sequences of the two genes as well as their 5' and 3'-flanking regions. Human 17 beta-HSDII contains six exons and five short introns for a total length of 3250 base pairs. The exon sequence of h17 beta-HSDII is identical to the previously reported hpE2DH216 cDNA while the overlapping nucleotide sequences of the corresponding exons and introns of h17 beta-HSDI and h17 beta-HSDII show 89% homology. In addition, we have used the hpE2DH216 cDNA to demonstrate the widespread expression of 17 beta-
HSD
mRNAs in steroidogenic and peripheral target tissues. These new findings provide the basis for a better understanding of the molecular mechanisms involved in 17 beta-
HSD
deficiency and peripheral sex steroid metabolism.
Mol
Endocrinol 1990 Feb
PMID:Structure of two in tandem human 17 beta-hydroxysteroid dehydrogenase genes. 233 5
The enzyme 3 beta-hydroxysteroid dehydrogenase (3 beta
HSD
) plays an essential role in the biosynthesis of all steroid hormones. We previously reported the isolation, characterization, and tissue-specific expression of four distinct but highly homologous 3 beta
HSD
cDNAs (forms I, II, III, and IV). Enzymatic characterization of three of these isoforms demonstrated that mouse 3 beta
HSD
I and III function as dehydrogenase/isomerases, but 3 beta
HSD
IV functions exclusively as a 3-ketosteroid reductase. We now report the isolation and characterization of an additional distinct mouse 3 beta
HSD
cDNA, 3 beta
HSD
V, which is expressed in the liver of male mice beginning in late puberty. Similar to 3 beta
HSD
IV, 3 beta
HSD
V functions exclusively as a 3-ketosteroid reductase converting an active androgen, dihydrotestosterone (DHT), into an inactive androgen, 5 alpha-androstane-3 beta,17 beta-diol. Expressed 3 beta
HSD
V, however, exhibits a considerably lower apparent Michaelis-Menten constant (Km) value for DHT than 3 beta
HSD
IV (0.47 microM vs. 2.2 microM, respectively). The complete predicted amino acid sequence of 3 beta
HSD
II is also reported. The predicted amino acid sequence of mouse 3 beta
HSD
V reveals that this new form is more closely related to the 3-ketosteroid reductases, mouse 3 beta
HSD
IV and rat III (93 and 84% identity, respectively), than to the other rodent isoforms that share less than 75% identity.(ABSTRACT TRUNCATED AT 250 WORDS)
Mol
Endocrinol 1995 Sep
PMID:The mouse 3 beta-hydroxysteroid dehydrogenase multigene family includes two functionally distinct groups of proteins. 749 Nov 13
We describe the cloning, sequencing and expression of the 3 alpha-hydroxysteroid dehydrogenase (3 alpha-
HSD
) gene of Pseudomonas testosteroni. A genomic library of P. testosteroni total DNA constructed from SauIIIA digests ligated to an lambda gt11 vector was probed with a polyclonal antibody raised against purified enzyme. Subclones derived from a recombinant phage containing a 1746 bp insert were sequenced and found to contain an open reading frame of 696 bp that corresponds to a protein of 231 amino acid residues. A search for homologous proteins was performed. No similarity was observed when comparing 3 alpha-
HSD
with known members of the short-chain dehydrogenase family. However a small proteic fragment (80 amino acids) shows homology with the N-terminal sequence of bacterial L7/L12 ribosomal proteins.
J Steroid Biochem
Mol
Biol 1995 Nov
PMID:Cloning, sequencing and expression of Pseudomonas testosteroni gene encoding 3 alpha-hydroxysteroid dehydrogenase. 749 3
A novel variant of 11 beta-hydroxysteroid dehydrogenase 1 (11 beta-HSD1) mRNA was identified from the ovine liver by reverse transcription-polymerase chain reaction (RT/PCR), and was named 11 beta-HSD1C mRNA. Sequence analysis of the RT-PCR product revealed that 11 beta-HSD1C mRNA was the product of an alternative exon-splicing within the 11 beta-HSD1 gene in which exon 5 was spliced out. Although it caused a deletion of 48 amino acids in the deduced 11 beta-HSD1 protein, this alternative splicing did not result in a shift within the predicted open reading frame of 11 beta-HSD1 cDNA. Thus, 11 beta-HSD1C mRNA was predicted to code for a protein of 244 amino acids. Using RT-PCR, we also examined the expression of 11 beta-HSD1C mRNA in ovine fetal organs and in maternal myometrium, endometrium, chorion, amnion and placenta. The 11 beta-HSD1C mRNA was expressed ubiquitously, similar to 11 beta-HSD1A mRNA, but at a lower abundance. Furthermore, since levels of 11 beta-HSD1C mRNA were directly related to those of 11 beta-HSD1A mRNA, there is no tissue-specificity for this shorter transcript and the only factor regulating its production appears to be 11 beta-HSD1A mRNA itself. To determine whether 11 beta-HSD1C mRNA encoded a functional enzyme, we inserted the cDNA into the expression vector pRc/CMV, and transfected the construct into Chinese hamster ovary cells. The transfected cells expressed a mRNA of expected size but contained no detectable 11 beta-
HSD
activity. When combined with cellular extracts of 11 beta-HSD1A cDNA transfected cells, they also did not alter either the dehydrogenase or reductase activity. The functional significance of the 11 beta-HSD1 transcript lacking exon 5 (11 beta-HSD1C mRNA) remains to be determined.
J Steroid Biochem
Mol
Biol 1995 Nov
PMID:Identification and tissue distribution of a novel variant of 11 beta-hydroxysteroid dehydrogenase 1 transcript. 749 5
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