Molecular cloning and functional characterization of peptidoglycan recognition protein 6 in grass carp Ctenopharyngodon idella
- Authors
- Li, J.H., Yu, Z.L., Xue, N.N., Zou, P.F., Hu, J.Y., Nie, P., and Chang, M.X.
- ID
- ZDB-PUB-131112-7
- Date
- 2014
- Source
- Developmental and comparative immunology 42(20): 244-255 (Journal)
- Registered Authors
- Nie, Pin
- Keywords
- peptidoglycan recognition protein, PGRP6, peptidoglycan-binding activity, antibacterial activity, grass carp, Ctenopharyngodon idella
- MeSH Terms
-
- Poly I-C/immunology
- Cell Line
- Nod2 Signaling Adaptor Protein/biosynthesis
- Nod2 Signaling Adaptor Protein/immunology
- Staphylococcus aureus/immunology
- Protein Binding
- Edwardsiella tarda/immunology
- Interleukin-2/biosynthesis
- Interleukin-2/immunology
- Teichoic Acids/immunology
- Molecular Sequence Data
- Carps/genetics
- Carps/immunology*
- Phylogeny
- Intestines/immunology
- Lipopolysaccharides/immunology
- Amino Acid Sequence
- Cloning, Molecular
- Base Sequence
- Bacillus subtilis/immunology
- Carrier Proteins/genetics*
- Carrier Proteins/immunology*
- Carrier Proteins/pharmacokinetics
- Enterobacteriaceae Infections/immunology*
- Fish Proteins/genetics
- Fish Proteins/immunology
- Liver/immunology
- Animals
- Peptidoglycan/immunology
- NF-kappa B/immunology*
- PubMed
- 24099967 Full text @ Dev. Comp. Immunol.
Peptidoglycan recognition proteins (PGRPs) are pattern recognition molecules of innate immunity. In this study, a long-form PGRP, designated as gcPGRP6, was identified from grass carp Ctenopharyngodon idella. The deduced amino acid sequence of gcPGRP6 is composed of 464 residues with a conserved PGRP domain at the C-terminus. The gcPGRP6 gene consists of four exons and three introns, spacing approximately 2.7 kb of genomic sequence. Phylogenetic analysis demonstrated that gcPGRP6 is clustered closely with zebrafish PGLYRP6, and formed a long-type PGRP subfamily together with PGLYRP2 members identified in teleosts and mammals. Real-time PCR and Western blotting analyses revealed that gcPGRP6 is constitutively expressed in organs/tissues examined, and its expression was significantly induced in liver and intestine of grass carp in response to PGN stimulation and in CIK cells treated with lipoteichoic acid (LTA), polyinosinic polycytidylic acid (Poly I:C) and peptidoglycan (PGN). Immunofluorescence microscopy and Western blotting analyses revealed that gcPGRP6 is effectively secreted to the exterior of CIK cells. The over-expression of gcPGRP6 in CIK cells leads to the activation of NF-κB and the inhibition of intracellular bacterial growth. Moreover, cell lysates from CIK cells transfected with pTurbo-gcPGRP6-GFP plasmid display the binding activity towards Lys-type PGN from Staphylococcus aureus and DAP-type PGN from Bacillus subtilis. Furthermore, proinflammatory cytokine IL-2 and intracellular PGN receptor NOD2 had a significantly increased expression in CIK cells overexpressed with gcPGRP6. It is demonstrated that the PGRP6 in grass carp has a role in binding PGN, in inhibiting the growth of intracellular bacteria, and in activating NF-κB, as well as in regulating innate immune genes.