Article

Characterization and antiviral function of a cytosolic sensor gene, MDA5, in Japanese flounder, Paralichthys olivaceus.

Aquatic Biotechnology Center, College of Veterinary Medicine, Gyeongsang National University, 900 Gajwa-dong, Jinju, Gyeongnam 660-710, South Korea.
Developmental and comparative immunology (impact factor: 3.29). 12/2010; 35(5):554-62. DOI:10.1016/j.dci.2010.12.013 pp.554-62
Source: PubMed

ABSTRACT Cytosolic pattern recognition receptors such as retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs) play an important role in sensing viral RNAs. The receptor encoded by melanoma differentiation-associated gene 5 (MDA5), an RLR, recognizes viral RNA in the cytoplasm and enhances antiviral response in host cells. The full-length MDA5 gene in Japanese flounder, Paralichthys olivaceus was cloned and found to have 11,251 nucleotides. MDA5 transcript abundance was significantly increased in whole kidney infected with viral hemorrhagic septicemia virus (VHSV) as well as whole kidney and peripheral blood leukocytes stimulated with poly I:C in vitro. Hirame natural embryo (HINAE) cells overexpressing MDA5 showed a lower cytopathic effect (CPE) against VHSV, hirame rhabdovirus (HIRRV) and infectious pancreatic necrosis virus (IPNV) infection. When infected with VHSV, MDA5-overexpressing HINAE cells had 24-75 fold lower virus titer than normal HINAE cells. These results suggest that Japanese flounder MDA5 is involved in the induction of antiviral response.

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Keywords

antiviral response
 
enhances antiviral response
 
full-length MDA5 gene
 
Hirame natural embryo
 
hirame rhabdovirus
 
host cells
 
infectious pancreatic necrosis virus
 
MDA5 transcript abundance
 
MDA5-overexpressing HINAE cells
 
melanoma differentiation-associated gene 5
 
normal HINAE cells
 
Paralichthys olivaceus
 
peripheral blood leukocytes
 
retinoic acid-inducible gene
 
RIG-I)-like receptors
 
RLR
 
RLRs
 
viral hemorrhagic septicemia virus
 
viral RNA
 
viral RNAs