Expression pattern of the single-minded gene in zebrafish embryos.
Recently we isolated a homolog of the Drosophila single-minded (sim) gene from a zebrafish cDNA library. The 4380-bp of zebrafish sim cDNA encodes a polypeptide of 585 amino acids with strikingly conserved bHLH and PAS A/B domains in the amino-terminal region. During embryogenesis, sim mRNA appears in the animal hemisphere as early as 3 h post-fertilization and is expressed in a widespread pattern throughout the epiblast at the 75% epiboly stage. During the segmentation stage, sim mRNA is prominently expressed in the primordium of the hindbrain and appears as a transverse stripe in the epithelial layers of the mid-diencephalic boundary (MDB). During the pharyngula stage, sim is no longer expressed in the hindbrain, but continues to be expressed in the MDB and extends to the caudal diencephalon along the ventral midline. In addition, sim mRNA is prominent in the two pharyngeal arches. During the larval stage, sim mRNA is transcribed in the esophagus, liver, pancreas, and intestine. In contrast, sim mRNA is no longer detectable in the forebrain after hatching. In adult fish, sim is widely expressed in brain, eyes, gill, heart, liver, and intestine.
Wen
Hui-Ju
HJ
Institute of Marine Biotechnology, National Taiwan Ocean University, No. 2, Pei-Ning Road, Keelung 202-24, Taiwan.
Wang
Ying
Y
Chen
Sei-Hui
SH
Hu
Chin-Hwa
CH
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D051792:Basic Helix-Loop-Helix Proteins; D018076:DNA, Complementary / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics*; D029721:Drosophila Proteins; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D007814:Larva / Q000254:growth & development / Q000378:metabolism; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics*; D009928:Organ Specificity; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015027:Zebrafish / Q000196:embryology* / Q000235:genetics* / Q000254:growth & development
D051792:Basic Helix-Loop-Helix Proteins; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D009687:Nuclear Proteins; D012333:RNA, Messenger; C089449:sim protein, Drosophila