Molecular cloning and expression of a novel CYP26 gene (cyp26d1) during zebrafish early development

Gene Expr Patterns. 2005 Aug;5(6):733-9. doi: 10.1016/j.modgep.2005.04.005.


Proper restriction of retinoid signaling by Cyp26s is essential for development of vertebrate embryos while inappropriate retinoid signaling can cause teratogenesis. Here, we report cloning and expression analysis of a novel cyp26 gene (cyp26d1) isolated from zebrafish. The predicted protein encoded by cyp26d1 consists of 554 amino acids. It exhibits 54% amino acid identity with human Cyp26C1, 50% with zebrafish Cyp26B1 and 38% with zebrafish Cyp26A1. Whole-mount in situ hybridization shows that cyp26d1 is first expressed in sphere stage, then disappears at 50% epiboly and resumes its expression at 75% epiboly. During segmentation period, cyp26d1 message is found at presumptive hindbrain. Double in situ hybridization with krox20 and cyp26d1 reveals that cyp26d1 is expressed in presumptive rhombomere 2-4 (r2-r4) at 2-somite stage. At 3-somite stage, cyp26d1 gene is expressed in r6 and pharyngeal arch (pa) one in addition to its expression at r2 and r4. At 6-somite stage, cyp26d1 message is present in continuous bands at r2-r6 and in pa1. This expression pattern is maintained from 10-somite stage through 21-somite stage except that the expression level is greatly reduced at r2 and r4. At 21-somite stage, cyp26d1 is also found in a group of cells in telencephalon and diencephalons. At 25-31h post-fertilization (hpf), the zebrafish cyp26d1 expression domain is extended to eyes, otic vesicles and midbrain in addition to its expression in hindbrain, telencephalon, diencephalons, and pharyngeal arches. At 35-48hpf, the expression of cyp26d1 is mainly restricted to otic vesicles, pharyngeal arches and pectoral fins and the expression level is greatly reduced.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Body Patterning
  • Cloning, Molecular
  • Conserved Sequence
  • Cytochrome P-450 Enzyme System / genetics*
  • DNA, Complementary / genetics
  • Embryo, Nonmammalian / enzymology
  • Gene Expression Regulation, Developmental*
  • Gene Expression Regulation, Enzymologic
  • Molecular Sequence Data
  • Morphogenesis
  • Retinoic Acid 4-Hydroxylase
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Zebrafish / embryology*
  • Zebrafish Proteins / genetics*


  • DNA, Complementary
  • Zebrafish Proteins
  • Cytochrome P-450 Enzyme System
  • cytochrome P-450 26D1, zebrafish
  • CYP26B1 protein, human
  • Retinoic Acid 4-Hydroxylase
  • cyp26a1 protein, zebrafish