摘要 : The cytoplasmic helicases retinoic acid-inducible gene I (RIG-I) and melanoma differentiation-associated protein 5 (MDA5) are two pattern recognition receptor genes belonging to RIG-I-like receptor (RLR). They play a crucial role ... 展开 The cytoplasmic helicases retinoic acid-inducible gene I (RIG-I) and melanoma differentiation-associated protein 5 (MDA5) are two pattern recognition receptor genes belonging to RIG-I-like receptor (RLR). They play a crucial role in host sensing of pathogen invasion. Herein, we identified and characterized complete cDNA of RIG-I and MDA5 in Chinese giant salamander (adRIG-I and adMDA5). To evaluate their expression levels, real-time fluorescence quantitative RT-PCR (qPCR) was performed between normal and Chinese giant salamander iridovirus (GSIV)-infected tissues. The full-length adMDA5 cDNA of 3,509 bp encoded a 968-acid amino polypeptide, and the 3567-bp adRIG-I cDNA encoded a 951-acid amino protein. The amino acid sequence analysis revealed adRIG-I and adMDA5 kept the conserved domains of RLR, and the two genes both shared relatively high similarity homologs with other species. Two genes were expressed in most tissues ofAndrias davidianus, with the highest expression in spleen. After GSIV infection, both adRIG-I and adMDA5 transcripts were initially increased then decreased in kidney and spleen. These results suggest that adRIG-I and adMDA5 can response to GSIV infection and may play a role in antiviral infections in DNA virus. 收起