Dengue virus (DENV) is a mosquito-borne flavivirus that causes the most prevalent diseases in tropical and subtropical regions. DENV utilizes host factors to facilitate its replication, while host cells intend to restrain virus replication. NS4A of DENV has been implicated to play a crucial role during viral replication. To identify more cellular proteins that are recruited by NS4A, we carried out a tandem affinity purification assay. The mass spectrometry data revealed that human eukaryotic initiation factor 4AI (eIF4AI) was one of potential NS4A-interacting partners. Co-immunoprecipitation data confirmed the interaction between NS4A and elF4AI, and both the N-terminal ATP-binding domain and C-terminal helicase domain of elF4A1 were involved in their association. Functionally, silencing of eIF4AI by RNAi significantly increased the replication level of DENV1, DENV2 and DENV3. And knockdown of elF4A1 markedly attenuated the phosphorylation of protein kinase regulated by dsRNA-activated (PKR) and elF2a induced by DENV2 infection. Collectively, these data suggested that a potential role of NS4A in antagonizing host antiviral defense is by recruiting elF4AI and escaping the translation inhibition mediated by PKR. (C) 2015 Elsevier Inc. All rights reserved.