Dengue Virus Targets the Adaptor Protein MITA to Subvert Host Innate Immunity

PLoS Pathogens

Tsung-Hsien Chang¹  Ching-Len Liao²  Chia-Yi Yu³  Yi-Ling Lin³  Ruei-Lin Chiang³  Jian-Jong Liang³  Yi-Ling Lee³ 

[1] Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan;Department of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan;Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan

关键词: Proteases;    Interferons;    Immunoprecipitation;    Transfection;    Viral replication;    Phosphorylation;    Immunoblotting;    Dengue fever;   

DOI  :  10.1371/journal.ppat.1002780

学科分类：生物科学（综合）

来源: Public Library of Science

【 摘 要 】

Dengue is one of the most important arboviral diseases caused by infection of four serotypes of dengue virus (DEN). We found that activation of interferon regulatory factor 3 (IRF3) triggered by viral infection and by foreign DNA and RNA stimulation was blocked by DEN-encoded NS2B3 through a protease-dependent mechanism. The key adaptor protein in type I interferon pathway, human mediator of IRF3 activation (MITA) but not the murine homologue MPYS, was cleaved in cells infected with DEN-1 or DEN-2 and with expression of the enzymatically active protease NS2B3. The cleavage site of MITA was mapped to LRR↓96G and the function of MITA was suppressed by dengue protease. DEN replication was reduced with overexpression of MPYS but not with MITA, while DEN replication was enhanced by MPYS knockdown, indicating an antiviral role of MITA/MPYS against DEN infection. The involvement of MITA in DEN-triggered innate immune response was evidenced by reduction of IRF3 activation and IFN induction in cells with MITA knockdown upon DEN-2 infection. NS2B3 physically interacted with MITA, and the interaction and cleavage of MITA could be further enhanced by poly(dA:dT) stimulation. Thus, we identified MITA as a novel host target of DEN protease and provide the molecular mechanism of how DEN subverts the host innate immunity.

【 授权许可】

CC BY