Sequence, linkage mapping and early developmental expression of the intestinal-type fatty acid-binding protein gene (fabp2) from zebrafish (Danio rerio)

Comp Biochem Physiol B Biochem Mol Biol. 2004 Aug;138(4):391-8. doi: 10.1016/j.cbpc.2004.05.009.


The intestinal fatty acid-binding protein (I-FABP) shows binding specificity for long-chain fatty acids and is proposed to be involved in uptake of dietary fatty acids and their intracellular transport. We have determined the sequence of the gene encoding I-FABP in zebrafish. The zebrafish I-FABP gene contains four exons interrupted by three introns. Radiation hybrid mapping assigned the I-FABP gene to linkage group 1. A 924 bp sequence 5' upstream of the initiation codon in the I-FABP gene contained several putative cis-acting regulatory elements. In adult zebrafish, reverse transcription-polymerase chain reaction (RT-PCR) detected I-FABP mRNA in intestine, brain, liver, muscle and testis. Quantitative RT-PCR demonstrated that I-FABP mRNA was most abundant in intestine, followed by brain. I-FABP mRNA levels were very low in muscle, testis, heart, liver, skin and ovary. RT-PCR using total RNA extracted from zebrafish embryos detected I-FABP mRNA as early as 12 h post-fertilization. Whole-mount in situ hybridization to zebrafish embryos detected I-FABP mRNA in the yolk syncytial layer (YSL) at early somitogenesis. Later during embryonic development the I-FABP mRNA was detected in the intestinal bulb, liver and pancreas primordium. Expression in YSL, liver or pancreas has not been previously reported for fish or mammalian I-FABP genes and may be related to specific physiological differences between fishes and mammals.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Carrier Proteins / biosynthesis*
  • Carrier Proteins / genetics*
  • Cloning, Molecular
  • Exons
  • Fatty Acid-Binding Proteins
  • Fatty Acids / chemistry
  • Genetic Linkage*
  • Introns
  • Molecular Sequence Data
  • Promoter Regions, Genetic
  • RNA / chemistry
  • RNA, Messenger / metabolism
  • Radiation Hybrid Mapping
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid
  • Time Factors
  • Tissue Distribution
  • Transcription, Genetic
  • Zebrafish
  • Zebrafish Proteins / biosynthesis*
  • Zebrafish Proteins / genetics*


  • Carrier Proteins
  • FABP2 protein, zebrafish
  • Fatty Acid-Binding Proteins
  • Fatty Acids
  • RNA, Messenger
  • Zebrafish Proteins
  • RNA