7-Dehydrocholesterol reductase

The 7-dehydrocholesterol reductase (abbreviation: DHCR7 or alternatively: 7- DHC reductase sterol delta ( 7) reductase D7SR ) is an enzyme in eukaryotes. It mediates the formation of cholesterol from 7-dehydrocholesterol and is therefore an important last enzyme in cholesterol biosynthesis. In human DHCR7 is mainly expressed in the adrenal glands, liver, testis and brain. It is there located in the membrane of the endoplasmic reticulum. Mutations in the gene DHCR7 with reduced enzyme activity lead to the Smith - Lemli -Opitz syndrome, a characteristic congenital malformation Retardierungssyndrom, which is associated biochemically with decreased cholesterol and increased 7- Dehydrocholesterinwerten.

Catalyzed reaction

NADH / H ⇔ ⇔ NAD

7- dehydrocholesterol is hydrogenated to cholesterol.

Genetics

The gene for DHCR7 encoded on chromosome 11q13.2 - 11q13.5 section, the enzyme itself is 475 amino acids long, weighs 54.5 kDa.

Human Genome Organisation
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