title: A second CYP26 P450 in humans and zebrafish: CYP26B1.
abstract: A new P450 gene has been found in humans. It has 44% sequence identity to CYP26A1 from human and mouse, which places it in a new subfamily, CYP26B. There is only one human EST from a retinal library (AA012833) that matches the coding region. No homologous ESTs are found in mouse. A zebrafish EST AI721901 shows 68% identity to the human protein. This zebrafish EST is only 41% identical to the zebrafish CYP26A1 protein sequence, so it represents the homolog of the human CYP26B1 sequence. It is not known if this gene product will act on all-trans-retinoic acid like the CYP26A1 protein or if it might hydroxylate the 9-cis- or 13-cis-retinoic acid isoforms not recognized by CYP26A1. The importance of the CYP26A1 P450 in mouse and zebrafish development flags the CYP26B1 gene as a potential developmental gene.
authors.affiliation: Department of Biochemistry, University of Tennessee, 858 Madison Avenue, Memphis, Tennessee 38163, USA. dnelson@utmem1.utmem.edu
authors.forename: D R
authors.initials: DR
authors.lastname: Nelson
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002874:Chromosome Mapping; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D020224:Expressed Sequence Tags; D006801:Humans; D007527:Isoenzymes / Q000235:genetics; D008969:Molecular Sequence Data; D000072516:Retinoic Acid 4-Hydroxylase; D017386:Sequence Homology, Amino Acid; D015027:Zebrafish; D029961:Zebrafish Proteins
chemical_list: D007527:Isoenzymes; D029961:Zebrafish Proteins; D003577:Cytochrome P-450 Enzyme System; C000607079:CYP26B1 protein, human; C000607080:Cyp26a1 protein, mouse; C000607081:Cyp26b1 protein, mouse; D000072516:Retinoic Acid 4-Hydroxylase; C000607085:cyp26a1 protein, zebrafish