Structural analysis of the intracellular RNAs of murine mammary tumor virus.

摘要: We have characterized murine mammary tumor virus (MuMTV)-specific RNA in several types of cells which viral DNA is transcribed into RNA: cultured GR mouse cells, S49 lymphoma from BALB/c mice, lactating glands C57BL/6 and mink lung infected vitro with MuMTV. In all cell studied, there are three distinct species intracellular RNA, sedimentation coefficients 35S, 24S, 13S (or molecular weights 3.1 X 10(6), 1.5 0.37 as determined by rate-zonal sucrose gradients electrophoresis agarose gels under denaturing conditions. These appear to be present regardless concentration, responsiveness glucocorticoid hormones, production extracellular virus, use either endogenous or acquired MuMTV proviral template. The RNAs display characteristics mRNAs that they polyadenylated, associated polyribosomes, released polyribosomes treatment EDTA; hence presumably direct the synthesis virus-coded proteins. two larger probably responsible for structural proteins virion, but function not known. Both subgenomic contain sequences found at 3' terminus 35S genomic) RNA. However, only 24S (not RNA) contains located 5' apparently transposed during maturation, described mRNA's other retroviruses.