Plays an essential role in nucleocapsid entry in host nucleus. May act by binding and stabilizing F-actin in the infected cell, which might attach to nucleocapsids and then push the nucleocapsids into the nucleus. Interacts with viral envelope protein E18 and the DNA-binding protein p6.9. Present in both the budded virus (BV) and the occluded virus (OV). The occluded form allows the virus to be transmitted from insect to insect through ingestion of contaminated food while the budded form is responsible for the dissemination of infection throughout the insect host. Contains a domain homologous to an NEBU domain that is known to bind actin.