The nuclear export signal (NES) of influenza A virus nuclear export protein (NEP) has been proposed to mediate the nuclear export of NEP and viral ribo nucleo protein (vRNP). However, much less is known about the nuclear export mechanism of influenza B virus NEP. In the present study, we identified three leucine-rich NESs (NES1, NES2, and NES3) in influenza B virus NEP. The intracellular distributions of green fluorescent protein (EGFP)-tagged wild type and NESs-mutant NEPs were determined. The results showed that the nuclear export of the NES1/NES2/NES3-mutant NEP was significantly decreased compared with that of the wild type NEP, suggesting that all three NESs are critical for NEP nuclear export. Furthermore, these three NESs regulated NEP nuclear export through CRM1-dependent manner and were necessary for influenza B virus replication. This study expands our understanding of the life cycle of influenza B virus by defining the nuclear export mechanism of influenza B virus NEP and could provide a scientific basis for the development of anti-influenza drugs.

Biography:
Dr. Wenhui Fan is an Assistant Professor at CAS Key Laboratory of Pathogenic Microbiology of Immunology, Institute of Microbiology, Chinese Academy of Science. She obtained her master degree from Ocean University of China in 2005 and got her doctoral degree from Guang Xi University in 2015. Her research focuses on the pathogenic mechanism of influenza A and B viruses, virus-host interaction, and development of antiviral drugs and biological products.