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25-Hydroxyvitamin D3 1-alpha-Hydroxylase MeSH Descriptor Data 2025


MeSH Heading
25-Hydroxyvitamin D3 1-alpha-Hydroxylase
Tree Number(s)
D08.244.453.499.500
D08.244.453.915.400
D08.811.682.690.708.170.493.500
D08.811.682.690.708.170.915.400
D12.776.422.220.453.499.500
D12.776.422.220.453.915.400
Unique ID
D015090
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D015090
Scope Note
A mitochondrial cytochrome P450 enzyme that catalyzes the 1-alpha-hydroxylation of 25-hydroxyvitamin D3 (also known as 25-hydroxycholecalciferol) in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP27B1 gene, converts 25-hydroxyvitamin D3 to 1-alpha,25-dihydroxyvitamin D3 which is the active form of VITAMIN D in regulating bone growth and calcium metabolism. This enzyme is also active on plant 25-hydroxyvitamin D2 (ergocalciferol).
Entry Term(s)
25-Hydroxycholecalciferol 1-Hydroxylase
25-Hydroxycholecalciferol-1-Hydroxylase
25-Hydroxyergocalciferol 1-alpha-Hydroxylase
25-Hydroxyvitamin D 1-alpha-Hydroxylase
25-Hydroxyvitamin D(3) 1 alpha-Hydroxylase
25-Hydroxyvitamin D2 1-hydroxylase
CYP27B1
Calcidiol 1-Monooxygenase
Cytochrome P-450 CYP27B1
Registry Numbers
EC 1.14.15.18
CAS Type 1 Name
Calcidiol,NADPH:oxygen oxidoreductase (1-hydroxylating)
Previous Indexing
Hydroxycholecalciferols (1973-1974)
Steroid Hydroxylases (1973-1974)
Public MeSH Note
2003; see 25-HYDROXYCHOLECALCIFEROL 1-HYDROXYLASE 1991-2002, see STEROID HYDROXYLASES 1975-1990; 25-HYDROXYVITAMIN D2 1-HYDROXYLASE was indexed under STEROID HYDROXYLASES 1976-2002
History Note
2003 (1975); for 25-HYDROXYVITAMIN D2 1-HYDROXYLASE use STEROID HYDROXYLASES (NM) 1976-2002
Date Established
1991/01/01
Date of Entry
1974/11/19
Revision Date
2019/04/29
25-Hydroxyvitamin D3 1-alpha-Hydroxylase Preferred
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