Center for Bioinformatics
Oxidoreductases | Transferases | Hydrolases | Lyases | Isomerases | Ligases

Basic Information

Enzyme Number

1.1.1.145/5.3.3.1

Official Name

steroid Delta-isomerase

Name from literature

beta hydroxysteroid dehydrogenase/isomerase

Pathway from literature

sex steroid production from pregnenolone

Pathway from KEGG

Lipid Metabolism; Androgen and estrogen metabolism; map00150

Lipid Metabolism; C21-Steroid hormone metabolism; map00140

Organisms

Human (9606)

Genome localization

1p13.1[3283 ], 1p13.1[3284 ],

Comments

May be at least three distinct enzymes.

Rate-limiting Description

"Hydroxyflutamide a specific androgen receptor (AR) antagonist, and cyproterone acetate or trilostane, both inhibitors of 3 beta-hydroxysteroid dehydrogenase/delta 4,5 isomerase, the rate-limiting enzyme for the conversion of DHEA to sex steroids, did not affect the ability of DHEA to downregulate GnRH gene expression." (12782399)

"Since isomerization appeared not to be the rate-limiting step of the overall reaction, measurement of activity of delta5-3beta-hydroxysteroid dehydrogenase was related to the amount of delta4-3-oxosteroid produced from the corresponding delta5-3beta-hydroxysteroid." (239964)

Regulatory Information

Upstream transcription factor

2494;3164;1051;100125288

Regulatory type

Detail

transcriptional factor;nerve growth factor-induced clone B family of transcription factors(3164)

"HSD3B2 is upregulated by the nerve growth factor-induced clone B family of transcription factors." (15615861)

key enzyme;

"The enzyme 3beta-hydroxysteroid dehydrogenase (3beta-HSD) is a key enzyme in the biosynthesis of steroid hormones. " (9075693)

inhibitor;

"Substantially higher affinity of 3beta-HSD1 activity for substrate and inhibitor steroids relative to the 3beta-HSD2 enzyme." (12530651)

inhibitor;

"Substantially higher affinity of 3beta-HSD1 activity for substrate and inhibitor steroids relative to the 3beta-HSD2 enzyme." (12530651)

transcriptional factor;LRH-1(2494)

"LRH-1 is highly expressed in corpus luteum, and it plays an essential role in the regulation of HSD3B2." (14671206)

transcriptional factor;NGFIB(3164)

"regulation of transcription by NGFIB" (15208301)

transcriptional factor;Nur77(3164)

"Nur77 is an important regulator of HSD3B2 promoter activity" (15498889)

transcriptional factor;the nerve growth factor-induced clone B family of transcription factor(3164)

"HSD3B2 is upregulated by the nerve growth factor-induced clone B family of transcription factors." (15615861)

transcriptional factor;"Transcription enhancer factor-5(1051),GATA-like protein(100125288)"

"Transcription enhancer factor-5 and the GATA-like protein act in a coordinate manner to determine the placental-specific expression of the human 3betaHSD I enzyme" (15131259)

transcriptional factor;NGFIB(3164)

"regulation of transcription by NGFIB" (15208301)

transcriptional factor;nerve growth factor-induced clone B family of transcription factor(3164)

"HSD3B2 is upregulated by the nerve growth factor-induced clone B family of transcription factors." (15615861)

Gene ontology

Gene ontology

GO:0006703 (P) estrogen biosynthetic process [P14060 ];
GO:0006700 (P) C21-steroid hormone biosynthetic process [P14060, P26439 ];
GO:0004769 (F) steroid delta-isomerase activity [P14060, P26439 ];
GO:0003854 (F) 3-beta-hydroxy-delta5-steroid dehydrogenase... [P14060, P26439 ];
GO:0016021 (C) integral to membrane [P14060, P26439 ];
GO:0030868 (C) smooth endoplasmic reticulum membrane [P14060, P26439 ];
GO:0005758 (C) mitochondrial intermembrane space [P14060, P26439 ];
GO:0005792 (C) microsome [P14060, P26439 ];
GO:0006702 (P) androgen biosynthetic process [P14060 ];
GO:0005488 (F) binding [P14060, P26439 ];
GO:0055114 (P) oxidation reduction [P14060, P26439 ];
GO:0005743 (C) mitochondrial inner membrane [P14060, P26439 ];

Tissue expression

Tissue From HPRD

Uterus [01941 ];
Intestine [01941 ];
Testis [01941 ];
Liver [01941 ];
Muscle [01941 ];
Brain [01941 ];
Prostate [01941, 04920 ];
Epididymis [01941 ];
Pulmonary artery [04920 ];
Adipose tissue [01941 ];
Kidney [01941 ];
Adrenal gland [01941 ];
Mammary gland [01941, 04920 ];
Heart [01941 ];
Lung [01941 ];
Ovary [01941 ];
Skin [01941, 04920 ];
Placenta [01941, 04920 ];
Vascular endothelium [04920 ];
Sebaceous gland [04920 ];
Pituitary gland [01941 ];

Tissue specificity

Adrenal glands, testes and ovaries [P26439 ];

Placenta and skin. Predominantly expressed in mammary gland tissue [P14060 ];

Subcellular localization

Localization

mitochondrion [P14060, P26439 ];

endoplasmic reticulum [P14060, P26439 ];

Disease relevance

Disease

Mild HSD3B2 deficiency in hyperandrogenic females is associated with characteristic traits of polycystic ovary syndrome, such as insulin resistance and luteinizing hormon hypersecretion [P26439 ];

Defects in HSD3B2 are the cause of adrenal hyperplasia type 2 (AH2) [MIM:201810]. AH2 is a form of congenital adrenal hyperplasia, a common recessive disease due to defective synthesis of cortisol. Congenital adrenal hyperplasia is characterized by androgen excess leading to ambiguous genitalia in affected females, rapid somatic growth during childhood in both sexes with premature closure of the epiphyses and short adult stature. Four clinical types: 'salt wasting' (SW, the most severe type), 'simple virilizing' (SV, less severely affected patients), with normal aldosterone biosynthesis, 'non-classic form' or late onset (NC or LOAH), and 'cryptic' (asymptomatic). In AH2, virilization is much less marked or does not occur. AH2 is frequently lethal in early life [P26439 ];

Links

SwissProt

P14060; P26439

Entrez Gene

3283; 3284; 3283; 3284

HPRD

04920; 04920; 01941; 01941



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  Last Modified: 2009-03-24  
  Design by Zhao Min