Gallus NME/NM23 nucleoside diphosphate kinase 2 interacts with viral σA and affects the replication of avian reovirus

Abstract Our present study aimed to identify host cell proteins that may interact with avian reovirus (ARV) σA protein and their potential effect on ARV replication. The ARV structural protein σA has been demonstrated to suppress interferon production and confirmed to activate the PI3K/Akt pathway. However, host cell factors interacting with σA to affect ARV replication remain unknown. In current study, a cDNA library of chicken embryo fibroblasts (CEFs) was constructed, and host cell proteins interacting with σA were screened by a yeast two-hybrid system. We identified four candidate cellular proteins that interact with ARV σA protein. Among them, Gallus NME/NM23 nucleoside diphosphate kinase 2 (NME2) was further validated as a σA-binding protein through co-immunoprecipitation. The key interaction domain was identified at amino acids (aa) 121-416 in NME2 and at aa 71-139 in σA, respectively. We demonstrated that overexpression of NME2 substantially inhibited ARV replication. In addition silencing NME2 by small interfering RNAs (siRNAs) resulted in marked enhancement of ARV replication. Our work has demonstrated that NME2 is a σA-binding protein that may affect ARV replication in CEF cells.