Region specific gene expressions in the central nervous system of the ascidian embryo.
The vertebrate brain is regionalized during development into forebrain, midbrain and hindbrain. Fibroblast growth factor 8 (FGF8) is expressed in the midbrain/hindbrain boundary (MHB) and functions as an organizer molecule. Previous studies demonstrated that the brain of basal chordates or ascidians is also regionalized at least into fore/midbrain and hindbrain. To better understand the ascidian brain regionalization, the expression of the Ciona Fgf8/17/18 gene was compared with the expression of Otx, En and Pax2/5/8 genes. The expression pattern of these genes resembled that of the genes in the vertebrate forebrain, midbrain, MHB and hindbrain, each of those domains being characterized by sole or combined expression of Otx, Pax2/5/8, En and Fgf8/17/18. In addition, the putative forebrain and midbrain expressed Ci-FgfL and Ci-Fgf9/16/20, respectively. Therefore, the regionalization of the ascidian larval central nervous system was also marked by the expression of Fgf genes.
Imai
Kaoru S
KS
Department of Zoology, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan. imai@ascidian.zool.kyoto-u.ac.jp
Satoh
Nori
N
Satou
Yutaka
Y
D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000196:embryology* / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D005346:Fibroblast Growth Factors / Q000235:genetics / Q000378:metabolism; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D009687:Nuclear Proteins; D051857:Otx Transcription Factors; D051762:PAX2 Transcription Factor; D051757:PAX5 Transcription Factor; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014561:Urochordata / Q000196:embryology* / Q000235:genetics / Q000378:metabolism
D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D009687:Nuclear Proteins; D051857:Otx Transcription Factors; D051762:PAX2 Transcription Factor; D051757:PAX5 Transcription Factor; D015534:Trans-Activators; D014157:Transcription Factors; C106185:engrailed homeobox proteins; D005346:Fibroblast Growth Factors