Duck RIG-I CARD Domain Induces the Chicken IFN-β by Activating NF-κB.
Retinoic acid-inducible gene I- (RIG-I-) like receptors (RLRs) have recently been identified as cytoplasmic sensors for viral RNA. RIG-I, a member of RLRs family, plays an important role in innate immunity. Although previous investigations have proved that RIG-I is absent in chickens, it remains largely unknown whether the chicken can respond to RIG-I ligand. In this study, the eukaryotic expression vectors encoding duRIG-I full length (duck RIG-I, containing all domains), duRIG-I N-terminal (containing the two caspase activation and recruitment domain, CARDs), and duRIG-I C-terminal (containing helicase and regulatory domains) labeled with 6∗His tags were constructed successfully and detected by western blotting. Luciferase reporter assay and enzyme-linked immunosorbent assay (ELISA) detected the duRIG-I significantly activated NF-κB and induced the expression of IFN-β when polyinosinic-polycytidylic acid (poly[I:C], synthetic double-stranded RNA) challenges chicken embryonic fibroblasts cells (DF1 cells), while the duRIG-I was inactive in the absence of poly[I:C]. Further analysis revealed that the CARDs (duRIG-I-N) induced IFN-β production regardless of the presence of poly[I:C], while the CARD-lacking duRIG-I (duRIG-I-C) was not capable of activating downstream signals. These results indicate that duRIG-I CARD domain plays an important role in the induction of IFN-β and provide a basis for further studying the function of RIG-I in avian innate immunity.
The Key Laboratory of Animal Genetics & Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou 225009, China.
Yang
Y
Chen
The Key Laboratory of Animal Genetics & Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou 225009, China.
Zhengyang
Z
Huang
The Key Laboratory of Animal Genetics & Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou 225009, China.
Bin
B
Wang
College of Animal Science and Technology, Jiangxi Agricultural University, Jiangxi 330045, China.
Qinming
Q
Yu
The Key Laboratory of Animal Genetics & Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou 225009, China.
Ran
R
Liu
The Key Laboratory of Animal Genetics & Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou 225009, China.
Qi
Q
Xu
The Key Laboratory of Animal Genetics & Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou 225009, China.
Guobin
G
Chang
The Key Laboratory of Animal Genetics & Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou 225009, China.
Jiatong
J
Ding
The Key Laboratory of Animal Genetics & Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou 225009, China.
Guohong
G
Chen
D000595:Amino Acid Sequence; D000818:Animals; D053468:CARD Signaling Adaptor Proteins / Q000235:genetics* / Q000378:metabolism; D002645:Chickens; D004372:Ducks; D005786:Gene Expression Regulation / Q000235:genetics; D007113:Immunity, Innate / Q000235:genetics*; D016899:Interferon-beta / Q000096:biosynthesis* / Q000235:genetics; D016328:NF-kappa B / Q000096:biosynthesis* / Q000235:genetics; D020365:RNA Helicases / Q000235:genetics* / Q000378:metabolism; D012367:RNA, Viral / Q000235:genetics
D053468:CARD Signaling Adaptor Proteins; D016328:NF-kappa B; D012367:RNA, Viral; D016899:Interferon-beta; D020365:RNA Helicases