Unique property of liver mitochondrial P450 to catalyze the two physiologically important reactions involved in both cholesterol catabolism and vitamin D activation.
The cDNA for vitamin D 25-hydroxylase in rat liver mitochondria was transfected in COS cells in order to confirm our previous postulation that both 5 beta-cholestane-3 alpha, 7 alpha, 12 alpha-triol 27-hydroxylation and vitamin D 25-hydroxylation are catalyzed by a common enzyme. As a result it was found that both enzyme activities could be reconstituted from the solubilized extract of mitochondria of these cells, NADPH, NADPH-adrenodoxin reductase and adrenodoxin, giving unequivocal evidence that the two enzyme activities are catalyzed by a common enzyme.
Usui
E
E
Department of Biochemistry, Hiroshima University School of Dentistry, Japan.
Noshiro
M
M
Ohyama
Y
Y
Okuda
K
K
D015090:25-Hydroxyvitamin D3 1-alpha-Hydroxylase / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D015153:Blotting, Western; D002460:Cell Line; D002784:Cholesterol / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D008930:Mitochondria, Liver / Q000201:enzymology*; D051381:Rats; D014162:Transfection; D014807:Vitamin D / Q000378:metabolism*
D014807:Vitamin D; D003577:Cytochrome P-450 Enzyme System; D002784:Cholesterol; D015090:25-Hydroxyvitamin D3 1-alpha-Hydroxylase