Selective recruitment of nucleoporins on vaccinia virus factories and the role of Nup358 in viral infection.

Vaccinia virus (VACV), a member of the Poxviridae family, uses cytoplasmic factories for its replication. Recent studies indicated that VACV infection requires a set of nucleoporins. However, how the nucleoporins contribute to viral life cycle remains unclear. Here, we report that the nucleoporins Nup62 and Nup358 localize to the cytoplasmic viral factories (VFs). Nup358 was targeted to the VFs at 6h post-infection (hpi), whereas Nup62, along with the previously reported translation factors such as eIF4E, eIF3η and G3BP1, was recruited to the VFs at 8 hpi. Nup358 depletion led to a decrease in the size and number of viral factories and reduction in viral yield. Further studies showed that Nup358 is involved in recruiting Nup62 and eIF4E to the VFs. Collectively, our results reveal spatio-temporal regulation in the recruitment of nucleoporins and translation factors to VFs, and particularly the importance of Nup358 in VACV infection.