Requirement of cell nucleus for the replication of an arenavirus.

Baby hamster kidney (BHK21) cells enucleated with cytochalasin B were infected with Pichinde virus or Sindbis virus. Viral replication was measured by plaque assay, and the synthesis of viral antigens was determined by immunofluorescence. Pichinde virus replication was completely inhibited in cells enucleated prior to infection as measured by both techniques while the replication of Sindbis virus was unaffected. Enucleation of cells at different times after infection with Pichinde virus indicated that intact nuclei were required for at least 8 h after infection.