title: Characterization of three Nod-like receptors and their role in antimicrobial responses of goldfish (Carassius auratus L.) macrophages to Aeromonas salmonicida and Mycobacterium marinum.
abstract: The nucleotide-binding oligomerization domain proteins Nod1, Nod2 and Nlrx1 are cytoplasmic pathogen recognition receptors (PRRs) of the Nod-like receptor (NLR) family. In this report, goldfish Nod1 (gfNod1), Nod2 (gfNod2) and Nlrx1 (gfNlrx1) genes were cloned and characterized. The full length of gfNod1, gfNod2 and gfNlrx1 were 3234bp, 3129bp and 4900bp, encoding 937, 982 and 1008 amino acids, respectively. The three Nod-like receptors have a NACHT domain and C-terminal leucine rich repeat (LRR) domains. In addition to these, gfNod1 and gfNod2 also had an N-terminal CARD domain (two in gfNod2). Phylogenetic analysis showed that the three NLRs are highly conserved. Quantitative gene expression analysis of the three receptors revealed the greatest mRNA levels in the spleen, and in isolated neutrophils and splenocytes. Furthermore, treatment of goldfish macrophages with LPS, Poly I:C, MDP, PGN, heat-killed Aeromonas salmonicida or Mycobacterium marinum differentially altered the expression of the Nod-like receptors. Our results indicate that Nod-like receptors are functionally highly conserved and that they play a pivotal role in recognition of fish pathogens such as A. salmonicida and M. marinum.
authors.affiliation: Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Jiasong
authors.initials: J
authors.lastname: Xie
authors.forename: Jordan W
authors.initials: JW
authors.lastname: Hodgkinson
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Katzenback
authors.forename: Nikolina
authors.initials: N
authors.lastname: Kovacevic
authors.forename: Miodrag
authors.initials: M
authors.lastname: Belosevic
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics; D048409:Aeromonas salmonicida / Q000276:immunology*; D000818:Animals; D051017:Apoptosis Regulatory Proteins / Q000235:genetics; D053468:CARD Signaling Adaptor Proteins / Q000235:genetics; D002478:Cells, Cultured; D003001:Cloning, Molecular; D029941:Fish Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000276:immunology; D006054:Goldfish / Q000276:immunology* / Q000382:microbiology; D016905:Gram-Negative Bacterial Infections / Q000276:immunology / Q000662:veterinary*; D007110:Immunity, Active; D008070:Lipopolysaccharides / Q000276:immunology; D008264:Macrophages / Q000276:immunology* / Q000382:microbiology; D024101:Mitochondrial Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D009165:Mycobacterium Infections, Nontuberculous / Q000276:immunology / Q000662:veterinary*; D019910:Mycobacterium marinum / Q000276:immunology*; D000070576:NLR Proteins; D053474:Nod1 Signaling Adaptor Protein / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D053473:Nod2 Signaling Adaptor Protein / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D010802:Phylogeny; D011070:Poly I-C / Q000276:immunology; D016415:Sequence Alignment; D014613:Vaccines, Attenuated
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D051017:Apoptosis Regulatory Proteins; D053468:CARD Signaling Adaptor Proteins; D029941:Fish Proteins; D008070:Lipopolysaccharides; D024101:Mitochondrial Proteins; D000070576:NLR Proteins; C427903:NLRP1 protein, human; C527006:NLRX1 protein, human; D053474:Nod1 Signaling Adaptor Protein; D053473:Nod2 Signaling Adaptor Protein; D014613:Vaccines, Attenuated; D011070:Poly I-C