title: Mechanism of early and late polykaryocytosis induced by the bovine leukaemia virus.
abstract: Syncytia formation induced by the bovine leukaemia virus (BLV) has been classified as 'early' or 'late' polykaryocytosis. Early polykaryocytosis arises in the first 24 h in mixed cultures of BLV-infected cells with indicator cells. Late polykaryocytosis is observed 4 to 8 days after infection of sensitive cells with cell-free infectious BLV. Our results demonstrate that the two phenomena proceed from different mechanisms. Late polykaryocytosis results from an active process dependent on the integrity of the virus genome. In contrast, early polykaryocytosis is a passive process which does not require any de novo virus synthesis but is dependent on the presence of virus proteins in inducer cells.
mesh_terms: D000818:Animals; D002417:Cattle; D002459:Cell Fusion; D002460:Cell Line; D003588:Cytopathogenic Effect, Viral; D005814:Genes, Viral; D001909:Leukemia Virus, Bovine / Q000235:genetics / Q000502:physiology*; D012190:Retroviridae / Q000502:physiology*; D013997:Time Factors; D014764:Viral Proteins / Q000502:physiology
chemical_list: D014764:Viral Proteins