Structural characterization of the gene encoding rat 25-hydroxyvitamin D3 24-hydroxylase.
The structural gene encoding 25-hydroxyvitamin D3 24-hydroxylase (P-450cc24) was isolated from the rat genomic DNA. It spans approximately 15 kb, is composed of 12 exons, and was demonstrated by Southern blot analysis to be present as a single copy. One major T residue was identified at the cap site, a putative TATA (ATAAATA) box was located at position -30, and a putative CCAAT box was at -58. Four possible vitamin D responsive elements that may be involved in regulation of 24-hydroxylase expression were found in the 5'-flanking region. Alignment with mitochondrial P-450 proteins showed that 7 out of 11 intron insertion sites of P-450cc24 gene occupied positions identical with those in the CYP11 family (P-450scc, P-450(11 beta)). The structure of the gene is discussed in relation to present knowledge about the mechanism of regulation of the 25-hydroxyvitamin D3 24-hydroxylase and calcium homeostasis.
Ohyama
Y
Y
Department of Biochemistry, Hiroshima University School of Dentistry, Japan.
Noshiro
M
M
Eggertsen
G
G
Gotoh
O
O
Kato
Y
Y
Björkhem
I
I
Okuda
K
K
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D002786:Cholesterol Side-Chain Cleavage Enzyme / Q000235:genetics; D019405:Cytochrome P-450 CYP11B2; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry / Q000235:genetics*; D004247:DNA / Q000737:chemistry*; D005091:Exons; D005796:Genes; D007438:Introns; D008928:Mitochondria / Q000201:enzymology; D008969:Molecular Sequence Data; D051381:Rats; D017208:Rats, Wistar; D017386:Sequence Homology, Amino Acid; D013250:Steroid Hydroxylases / Q000737:chemistry / Q000235:genetics*; D014158:Transcription, Genetic; D065668:Vitamin D3 24-Hydroxylase
D004247:DNA; D003577:Cytochrome P-450 Enzyme System; D013250:Steroid Hydroxylases; D065668:Vitamin D3 24-Hydroxylase; D019405:Cytochrome P-450 CYP11B2; D002786:Cholesterol Side-Chain Cleavage Enzyme