Biomaterial Database

[Genetic control of the activity of microsomal enzymes of steroidogenesis in Leydig cells of inbred strains of mice]. 1998

A V Osadchuk, and K V Svechnikov

Institute of Cytology and Genetics, Siberian Division, Russian Academy of Sciences, Novosibirsk, Russia.

Four activities of key microsomal steroidogenic enzymes (3 beta-hydroxysteroid dehydrogenase-isomerase, microsomal cytochrome P45017 beta, and 17-ketosteroid reductase) were compared in Leydig cells of six inbred strains of mice: A/He, CBA/Lac, C57BL/6J, DD, YT, and PT. The activities of the enzymes were found to vary considerably from one strain to another, depending on the genotype. Analysis of testosterone biosynthesis revealed a decreased activity of 17-ketosteroid reductase as compared to the activities of other microsomal steroidogenic enzymes. The metabolism of pregnenolone and progesterone demonstrated features dependent on the genotype and caused by genotypic differences in the activities of microsomal steroidogenic enzymes. These activities demonstrated a correlative interstrain variation indicative of their coordinated genetic control. The correlative variation may be related to a major gene effect on the activities of microsomal steroidogenic enzymes.

UI	MeSH Term	Description	Entries
D007985	Leydig Cells	Steroid-producing cells in the interstitial tissue of the TESTIS. They are under the regulation of PITUITARY HORMONES; LUTEINIZING HORMONE; or interstitial cell-stimulating hormone. TESTOSTERONE is the major androgen (ANDROGENS) produced.	Interstitial Cells, Testicular,Leydig Cell,Testicular Interstitial Cell,Testicular Interstitial Cells,Cell, Leydig,Cell, Testicular Interstitial,Cells, Leydig,Cells, Testicular Interstitial,Interstitial Cell, Testicular
D008297	Male		Males
D008815	Mice, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations, or by parent x offspring matings carried out with certain restrictions. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.	Inbred Mouse Strains,Inbred Strain of Mice,Inbred Strain of Mouse,Inbred Strains of Mice,Mouse, Inbred Strain,Inbred Mouse Strain,Mouse Inbred Strain,Mouse Inbred Strains,Mouse Strain, Inbred,Mouse Strains, Inbred,Strain, Inbred Mouse,Strains, Inbred Mouse
D008861	Microsomes	Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)	Microsome
D011284	Pregnenolone	A 21-carbon steroid, derived from CHOLESTEROL and found in steroid hormone-producing tissues. Pregnenolone is the precursor to GONADAL STEROID HORMONES and the adrenal CORTICOSTEROIDS.	5-Pregnen-3-beta-ol-20-one,5 Pregnen 3 beta ol 20 one
D011374	Progesterone	The major progestational steroid that is secreted primarily by the CORPUS LUTEUM and the PLACENTA. Progesterone acts on the UTERUS, the MAMMARY GLANDS and the BRAIN. It is required in EMBRYO IMPLANTATION; PREGNANCY maintenance, and the development of mammary tissue for MILK production. Progesterone, converted from PREGNENOLONE, also serves as an intermediate in the biosynthesis of GONADAL STEROID HORMONES and adrenal CORTICOSTEROIDS.	Pregnenedione,Progesterone, (13 alpha,17 alpha)-(+-)-Isomer,Progesterone, (17 alpha)-Isomer,Progesterone, (9 beta,10 alpha)-Isomer
D005838	Genotype	The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.	Genogroup,Genogroups,Genotypes
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013254	Steroid 17-alpha-Hydroxylase	A microsomal cytochrome P450 enzyme that catalyzes the 17-alpha-hydroxylation of progesterone or pregnenolone and subsequent cleavage of the residual two carbons at C17 in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP17 gene, generates precursors for glucocorticoid, androgen, and estrogen synthesis. Defects in CYP17 gene cause congenital adrenal hyperplasia (ADRENAL HYPERPLASIA, CONGENITAL) and abnormal sexual differentiation.	17 alpha-Hydroxylase,17,20-Lyase,CYP17,Cytochrome P-450(17 alpha),P450(c17),Steroid 17 alpha-Monooxygenase,Steroid 17-Hydroxylase,Steroid 17-Monooxygenase,17 alpha-Hydroxylase Cytochrome P-450,17 alpha-Hydroxyprogesterone Aldolase,17,20-Desmolase,Cytochrome P-450(17-alpha),Cytochrome P450(17 alpha),Hydroxyprogesterone Aldolase,Steroid 17 alpha-Hydroxylase,Steroid-17-Hydroxylase,17 alpha Hydroxylase,17 alpha Hydroxylase Cytochrome P 450,17 alpha Hydroxyprogesterone Aldolase,17 alpha-Hydroxylase, Steroid,17 alpha-Monooxygenase, Steroid,17,20 Desmolase,17,20 Lyase,17-Hydroxylase, Steroid,17-Monooxygenase, Steroid,17-alpha-Hydroxylase, Steroid,Aldolase, 17 alpha-Hydroxyprogesterone,Aldolase, Hydroxyprogesterone,Steroid 17 Hydroxylase,Steroid 17 Monooxygenase,Steroid 17 alpha Hydroxylase,Steroid 17 alpha Monooxygenase,alpha-Hydroxyprogesterone Aldolase, 17,alpha-Monooxygenase, Steroid 17
D013256	Steroids	A group of polycyclic compounds closely related biochemically to TERPENES. They include cholesterol, numerous hormones, precursors of certain vitamins, bile acids, alcohols (STEROLS), and certain natural drugs and poisons. Steroids have a common nucleus, a fused, reduced 17-carbon atom ring system, cyclopentanoperhydrophenanthrene. Most steroids also have two methyl groups and an aliphatic side-chain attached to the nucleus. (From Hawley's Condensed Chemical Dictionary, 11th ed)	Steroid,Catatoxic Steroids,Steroids, Catatoxic