title: Hepatitis delta antigen is necessary for access of hepatitis delta virus RNA to the cell transcriptional machinery but is not part of the transcriptional complex.
abstract: To examine the role of hepatitis delta virus antigen in the replication of hepatitis delta virus RNA, we have transfected a stable HDAg-positive cell line (A3) and the parental HDAg-negative line (HepG2) with HDV RNA produced in vitro; synthesis of complementary HDV RNA was only detected in HDAg-positive cultures. In contrast, nuclear homogenates from both HDAg-positive and -negative cells synthesized comparable levels of complementary RNA from exogenous HDV RNA. These findings indicate that HDAg is not a necessary component of the transcriptional complex and suggest with other evidence, that a major role for HDAg is likely to be transport of HDV RNA from cytoplasm to nucleus. Transcription of HDV RNA by intact nuclei was sensitive to 1 microgram/ml alpha-amanatin providing firm evidence that, like viroids, this function is performed by host RNA polymerase II.
authors.affiliation: Division of Medical Virology, Institute of Medical and Veterinary Science Frome Road, Adelaide, South Australia.
authors.forename: T B
authors.initials: TB
authors.lastname: MacNaughton
authors.forename: E J
authors.initials: EJ
authors.lastname: Gowans
authors.forename: S P
authors.initials: SP
authors.lastname: McNamara
authors.forename: C J
authors.initials: CJ
authors.lastname: Burrell
mesh_terms: D000546:Amanitins / Q000494:pharmacology; D000956:Antigens, Viral / Q000378:metabolism*; D006528:Carcinoma, Hepatocellular; D002460:Cell Line; D002472:Cell Transformation, Viral; D003698:Hepatitis Delta Virus / Q000235:genetics* / Q000502:physiology; D035923:Hepatitis delta Antigens; D006801:Humans; D008113:Liver Neoplasms; D012319:RNA Polymerase II / Q000378:metabolism; D012367:RNA, Viral / Q000235:genetics*; D014158:Transcription, Genetic / Q000187:drug effects; D014162:Transfection
chemical_list: D000546:Amanitins; D000956:Antigens, Viral; D035923:Hepatitis delta Antigens; D012367:RNA, Viral; C442244:hepatitis delta virus large antigen; D012319:RNA Polymerase II