title: Cellular localization of Saint Louis encephalitis virus replication.
abstract: Replication of Saint Louis encephalitis (SLE) virus was inhibited when PS cells were treated with actinomycin D, daunomycin or cordycepin during the first 9 hr after infection. Autoradiography of SLE virus-infected pulse labelled cells demonstrated that viral RNA synthesis is localized within the nuclear area. Nuclei purified from cells after 12 hr of infection contained heterogeneous 20 S to 26 S viral RNA but no SLE virus genome sized 43 S RNA. Later during infection, nuclei isolated from infected cells contained large amounts of 43 S and 20 S to 26 S RNAs. The 43 S viral RNA present in cells late in infection could not be removed with 1% Tween 80: Nonidet P 40. Purified nuclei isolated from cells early in infection supported the synthesis of 43 S virion RNA in the absence of cytoplasmic factors. The cytoplasmic membrane fraction prepared from cells early in infection contained heterogeneous 10 S to 26 S RNA species; later during infection these membranes contained viral 43 S, 26 S to 30 S and 4 S RNA. These results suggest that the nucleus is an important site of early viral synthesis.
mesh_terms: D000818:Animals; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism; D003609:Dactinomycin / Q000494:pharmacology; D003630:Daunorubicin / Q000494:pharmacology; D004665:Encephalitis Virus, St. Louis / Q000254:growth & development / Q000378:metabolism*; D004668:Encephalitis Viruses / Q000378:metabolism*; D000882:Haplorhini; D007668:Kidney; D012367:RNA, Viral / Q000096:biosynthesis*; D013552:Swine
chemical_list: D012367:RNA, Viral; D003609:Dactinomycin; D003630:Daunorubicin