Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:1.1.1.3 (
HSD
)
3,464
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
3 alpha-Hydroxysteroid dehydrogenase (3 alpha-
HSD
) [EC 1.1.1.213]2 plays important multifunctional roles in metabolizing steroid hormones, polycyclic aromatic hydrocarbons, and prostaglandins and also in transforming the steroid nucleus for the biosynthesis of bile acids from cholesterol in liver. To gain insight into the details and physiological functions of 3 alpha-
HSD
in the bile acid biosynthetic pathway, cDNA clones of 3 alpha-
HSD
were isolated from rat liver lambda phage cDNA libraries by using specific antibodies to 3 alpha-
HSD
purified from rat liver. Transfection of the 3 alpha-
HSD
cDNA in Simian COS7 cells resulted in the expression of an immunoreactive protein to the antibodies against the purified enzyme, and the transfected cells exhibited activities for not only 7 alpha-hydroxy-5 beta-
cholestan-3-one
, the intermediate of bile acid biosynthesis, but also steroid hormones and 9,10-phenanthrenequinone. Northern blot analysis on poly(A)+ RNA by selective use of different cDNA fragments of the 5'-untranslated region, the coding region, and the 3'-untranslated region as probes revealed three hybridizable bands, 3.6, 2.7, and 2.5 kb, in liver and four bands, 3.6, 2.7, 2.5, and 1.8 kb, in ovary. Of these, the 2.7- and 1.8-kb bands were predominant in liver and ovary, respectively. Northern hybridization analysis also revealed that the coding region of the various sizes of mRNA seemed to be common. Southern blot analysis of genomic DNA by the selective use of the cDNA fragments as probes indicated that the various mRNA species were derived from a single gene, probably due to an alternative splicing mechanism.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Rat hepatic 3 alpha-hydroxysteroid dehydrogenase: expression of cDNA and physiological function in bile acid biosynthetic pathway. 751 72