The antigen receptor (NCCRP-1) on catfish and zebrafish nonspecific cytotoxic cells belongs to a new gene family characterized by an F-box-associated domain.

Abstract

The catfish nonspecific cytotoxic cell receptor protein (NCCRP-1) provides an important function in target cell recognition and activation of cytotoxicity. This report identifies and characterizes a zebrafish orthologue of the catfish NCCRP-1. The zebrafish NCCRP-1 cDNA contains an open reading frame that encodes a predicted protein of 237 amino acids with a MW of 27 kDa and a pI of 5.5. Sequence similarities comparisons show that the NCCRP-1 receptors from these two phylogenetically distant species share a high degree of identity. These results suggested that NCCRP-1 performs a crucial function in innate immunity in teleosts. Further, a zebrafish 17-mer peptide corresponding to the catfish NCCRP-1 antigen-binding domain inhibited (catfish) cytotoxicity toward conventional tumor target cells (HL-60). These data appeared to indicate that the zebrafish NCCRP-1 protein may function as an antigen recognition molecule and, as such, may participate in innate immunity in teleosts. A homology search of the zebrafish NCCRP-1 protein revealed that it shares a significant level of identity with another group of proteins belonging to an F-box subfamily. These proteins share an F-box domain in the N terminus (not present in NCCRP-1) and an extremely conserved C-terminal region that has been termed the F-box-associated domain (FBA). The FBA is currently of unknown function. A new gene family is proposed in this work, based on similarities in the FBA sequences with the catfish and zebrafish NCCRP-1 peptides. This new gene family includes several F-box domain-containing proteins and a predicted C. elegans protein.

• Authors: Liliana Jaso-Friedmann, David S Peterson, Daniel S Gonzalez, Donald L Evans
• Journal: Journal of molecular evolution (J Mol Evol) Vol. 54 Issue 3 Pg. 386-95 (Mar 2002) ISSN: 0022-2844 [Print] Germany
• PMID: 11847564 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.)

Chemical References

• Receptors, Antigen
• nonspecific cytotoxic cell receptor protein 1

Topics

• Amino Acid Motifs (genetics)
• Amino Acid Sequence
• Animals
• Base Sequence
• Catfishes (genetics, immunology)
• Consensus Sequence (genetics)
• Evolution, Molecular
• Killer Cells, Natural (immunology)
• Molecular Sequence Data
• Phylogeny
• Protein Structure, Tertiary (genetics)
• Receptors, Antigen (genetics)
• Sequence Alignment
• Sequence Analysis, DNA
• Zebrafish (genetics, immunology)