Expression of the FGF receptor 2 gene (fgfr2) during embryogenesis in the zebrafish Danio rerio.
We isolated a full-length cDNA clone for the zebrafish homologue of fibroblast growth factor receptor (FGFR) 2. The deduced protein sequence is typical of vertebrate FGFRs in that it has three Ig-like domains in the extracellular region. The expression of fgfr2 is initiated during epiboly in the paraxial mesoderm. During early somitogenesis, fgfr2 expression was noted in the anterior neural plate as well as in newly formed somites. Whereas fgfr2 expression in somites is transient, it increases in the central nervous system (CNS), i.e. in the ventral telencephalon, anterior diencephalon, midbrain, and respective rhombomeres of the hindbrain, from the mid-somitogenesis stage. The dorsal telencephalon and the region around the midbrain-hindbrain boundary are devoid of fgfr2 expression. Essentially the same expression pattern is observed until 48 h post-fertilization in the CNS, although rhombomeric expression in the hindbrain is progressively confined to narrower stripes. After somitogenesis, fgfr2 expression was also observed in the lens, hypochord, endoderm, and fin mesenchyme. We compared the expression of the four fgfr genes (fgfr1-4) in the CNS of zebrafish embryos and show that fgfr1 is the only fgfr gene that is expressed in the dorsal telencephalon and isthmic region from which expression of fgfr2-4 is absent.
Tonou-Fujimori
Noriko
N
Department of Regulation Biology, Faculty of Science, Saitama University, 255 Shimo-Okubo, Saitama City, Saitama 338-8570, Japan.
Takahashi
Masayoshi
M
Onodera
Hiroshi
H
Kikuta
Hiroshi
H
Koshida
Sumito
S
Takeda
Hiroyuki
H
Yamasu
Kyo
K
D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D008969:Molecular Sequence Data; D020794:Receptor Protein-Tyrosine Kinases / Q000096:biosynthesis / Q000235:genetics*; D051497:Receptor, Fibroblast Growth Factor, Type 2; D017468:Receptors, Fibroblast Growth Factor / Q000096:biosynthesis / Q000235:genetics*; D016415:Sequence Alignment; D020539:Sequence Analysis, Protein; D015027:Zebrafish / Q000196:embryology / Q000235:genetics*; D029961:Zebrafish Proteins / Q000096:biosynthesis / Q000235:genetics
D017468:Receptors, Fibroblast Growth Factor; D029961:Zebrafish Proteins; D020794:Receptor Protein-Tyrosine Kinases; D051497:Receptor, Fibroblast Growth Factor, Type 2; C496358:fgfr2 protein, zebrafish