title: Isolation of a transcriptive complex from Newcastle disease virions.
abstract: An active transcriptive complex was isolated from purified virions of Newcastle disease virus. After disruption with Triton X-100 and high salt, soluble and particulate fractions were separated by density gradient centrifugation. The transcriptive complex, recovered at a density of 1.275 g/cm3, appeared as a nucleocapsid structure by electron microscopy. When analyzed by polyacryl-amide gel electrophoresis, the nucleocapsids consisted of the nucleocapsid protein, a minor protein of 53,000 molecular weight, and the large L protein. Nucleocapsids possessed less than 1% of the hemagglutinating and neuraminidase activities originally associated with virions. The active complex synthesized predominantly 11 to 20S RNA in vitro and approximately one-fourth of the RNA molecules contained polyadenylic acid segments. In the presence of S-adenosyl-L-methionine, the RNA molecules were capped and methylated at the 5' termini. The transcriptive complex was also capable of methylating exogenous Escherichia coli RNA in the absence of viral RNA synthesis.
mesh_terms: D002213:Capsid / Q000032:analysis; D002499:Centrifugation, Density Gradient; D008745:Methylation; D008854:Microscopy, Electron; D008970:Molecular Weight; D009522:Newcastle disease virus / Q000032:analysis* / Q000378:metabolism; D011061:Poly A / Q000032:analysis; D011092:Polyethylene Glycols; D012367:RNA, Viral / Q000032:analysis / Q000096:biosynthesis; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000032:analysis / Q000302:isolation & purification
chemical_list: D012367:RNA, Viral; D014764:Viral Proteins; D011061:Poly A; D011092:Polyethylene Glycols