Toll-like receptor gene family and TIR-domain adapters in Danio rerio

Mol Immunol. 2004 Jan;40(11):759-71. doi: 10.1016/j.molimm.2003.10.001.

Abstract

The toll-like family of receptors (TLR) is an ancient pattern recognition receptor family, conserved from insects to mammals. We have identified in zebrafish (Danio rerio) 19 putative TLR variants, the orthologs of mammalian TLR2-5, 7-9, a fish specific receptor type group and three putative splice variants. One receptor is very close to mammalian TLR1, 6 and 10 and seems to be their common ancestor. However, in contrast to the pufferfish, Fugu rubripes, we found two receptors homologous to TLR4, showing that lack of TLR4 is not general for fish. In addition, we identified two members close to mammalian TLR8 and five members close to FuguTLR21 and goldfish TLR, a TLR group which now has only been found in fish. By RT-PCR we showed that all TLR are widely expressed in adult tissues, but also at different stages of development. All these TLRs contain very conserved toll/interleukin-1 receptor (TIR) domains able to interact with TIR-domain of adapter molecules. We demonstrate here that TIR-domain containing adapters MyD88 and SARM are present in zebrafish, showing that TLR adapter molecules are highly conserved in evolution.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Evolution, Molecular
  • Membrane Glycoproteins / genetics*
  • Membrane Glycoproteins / physiology
  • Molecular Sequence Data
  • Multigene Family*
  • Phylogeny
  • Protein Structure, Tertiary
  • Receptors, Cell Surface / genetics*
  • Receptors, Cell Surface / physiology
  • Sequence Alignment
  • Sequence Analysis, Protein
  • Sequence Homology
  • Signal Transduction / genetics
  • Signal Transduction / physiology
  • Toll-Like Receptor 1
  • Toll-Like Receptor 2
  • Toll-Like Receptor 4
  • Toll-Like Receptor 8
  • Toll-Like Receptors
  • Zebrafish / genetics*
  • Zebrafish / physiology

Substances

  • Membrane Glycoproteins
  • Receptors, Cell Surface
  • Toll-Like Receptor 1
  • Toll-Like Receptor 2
  • Toll-Like Receptor 4
  • Toll-Like Receptor 8
  • Toll-Like Receptors