Rice yellow stunt virus p3 protein enters the nucleus of leafhopper cell and localizes to viroplasm through interaction with N protein via importin α3-mediated pathway

Abstract

Rice yellow stunt virus (RYSV) P3 protein functions as a movement protein during viral infection of a plant host; its function in insect hosts remains unclear. In this study, we investigated the subcellular localization of P3 using leafhopper (Nephotettix cincticeps) cell cultures. Our results showed that P3 translocated from the cytoplasm to the nucleus in RYSV-infected leafhopper cells, where it interacted with the viral N protein as a constituent of viroplasms. Interfering with the P3 gene expression significantly suppressed viral infection in N. cincticeps. Finally, we demonstrate that the nuclear translocation of P3 in leafhopper cells depended on its interaction with RYSV N protein, which enters the nucleus via an interaction with importin α3. These findings unveil a previously unknown role for P3 in RYSV infection of the insect vector and provide valuable insights into the infection dynamics of plant rhabdoviruses.