Pregn-5-ene-3,20-dione isomerizes to progesterone

Stable Identifier
Reaction [transition]
Homo sapiens
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Pregn-5-ene-3,20-dione isomerizes to progesterone. This reaction is catalyzed by the isomerase activity of 3 beta-HSD, associated with the endoplasmic reticulum membrane. The active form of the enzyme is a homodimer. The enzyme occurs in two isoforms that are similar in their biochemical properties but differ in their tissue expression: type I (HSD3B1) is found in placenta and skin, while type II (HSD3B2) is found in the adrenal glands and gonads.
The hormone lutropin (LH) triggers ovulation and development of the corpus luteum, that in turn increases production of progesterone.

Literature References
PubMed ID Title Journal Year
1944309 Structure and expression of a new complementary DNA encoding the almost exclusive 3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4-isomerase in human adrenals and gonads

Rheaume, E, Lachance, Y, Zhao, HF, Breton, N, Dumont, M, de Launoit, Y, Trudel, C, Luu-The, V, Simard, J, Labrie, F

Mol Endocrinol 1991
2770297 Human placental 3 beta-hydroxy-5-ene-steroid dehydrogenase and steroid 5----4-ene-isomerase: purification from mitochondria and kinetic profiles, biophysical characterization of the purified mitochondrial and microsomal enzymes

Thomas, JL, Myers, RP, Strickler, RC

J Steroid Biochem 1989
12832414 Structure/function relationships responsible for coenzyme specificity and the isomerase activity of human type 1 3 beta-hydroxysteroid dehydrogenase/isomerase

Thomas, JL, Duax, WL, Addlagatta, A, Brandt, S, Fuller, RR, Norris, W

J Biol Chem 2003
2243100 Characterization of human 3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4-isomerase gene and its expression in mammalian cells

Lachance, Y, Luu-The, V, Labrie, C, Simard, J, Dumont, M, de Launoit, Y, Guerin, S, Leblanc, G, Labrie, F

J Biol Chem 1990
Participant Of
Catalyst Activity
Catalyst Activity
steroid delta-isomerase activity of HSD2B1 or HSD3B2 dimer [endoplasmic reticulum membrane]
Physical Entity
This event is regulated
Orthologous Events
Cross References
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