title: RNA metabolism of murine leukemia virus. III. Identification and quantitation of endogenous virus-specific mRNA in the uninfected BALB/c cell line JLS-V9.
abstract: mRNA containing type C endogenous virus-specific sequences was indentified in JLS-V9 cells (an uninfected BALB/c-derived cell line) by annealing extracted RNA with 3H-labeled virus-specific DNA. The criterion for virus-specific RNA being mRNA was that it co-sedimented with polyribosomes in a sucrose gradient and that it changed to lower sedimentation value if polyribosomes were disagregated prior to centrifugation. It was not possible to identify virus-specific mRNA in unfractionated cytoplasm from JLS-V9 cells since large amounts of virus-specific ribonucleoprotein which was not mRNA had sedimentation values similar to polyribosomes and obscured the analysis. Virus-specific mRNA could be readily identified in polyribosomes which had been purified through a step gradient of 1 and 2 M sucrose, and consisted of two species with sedimentation values of 38S and 27S. The amount of virus-specific RNA in different JLS-V9 cell fractions was quantitated in comparison to cell fractions obtained from M-MuLV clone no. 1 cells (a line of NIH 3T3 cells producing Moloney murine leukemia virus). Approximately 40% of the total virus-specific mRNA was recovered in the purified polyribosomes in M-MuLV no. 1 cells. The amount of virus-specific RNA on polyribosomes appeared to be quite similar for JLS-V9 cells and M-MuLV clone no.1 cells . In contrast, the level of virus-specific protein in JLS-V9 cells (as monitored by radioimmunoassay of the internal structural protein p30) was less than 2% the level in the M-MuLV clone no. 1 cells.
mesh_terms: D000818:Animals; D002460:Cell Line; D003593:Cytoplasm / Q000032:analysis; D007065:Idoxuridine / Q000494:pharmacology; D009052:Leukemia Virus, Murine / Q000032:analysis*; D051379:Mice; D008815:Mice, Inbred Strains; D008979:Moloney murine leukemia virus / Q000032:analysis*; D011132:Polyribosomes / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis*; D012367:RNA, Viral / Q000032:analysis*; D012190:Retroviridae / Q000032:analysis*; D014764:Viral Proteins / Q000032:analysis
chemical_list: D012333:RNA, Messenger; D012367:RNA, Viral; D014764:Viral Proteins; D007065:Idoxuridine