title: Mouse mammary tumor virus-related sequences in mouse lymphocytes are inducible by 12-O-tetradecanoyl phorbol-13-acetate.
abstract: cDNA libraries from EL-4 cells treated with 12-O-tetradecanoyl phorbol-13-acetate (TPA) were screened for TPA-inducible sequences by differential hybridization. The most abundant inducible species was a sequence similar to that of mouse mammary tumor virus (MMTV). Induction of the mRNA corresponding to the MMTV-related sequences was already evident 30 min after TPA treatment, whereas the maximum accumulation occurred after 20 h of exposure to TPA. TPA also increased levels of MMTV-related RNA in the normal spleen cells of BALB/c and C57BL/6 mice. The level of RNA expression corresponding to MMTV-related sequences, however, was markedly elevated in EL-4 cells as compared with normal spleen cells. Southern blots of EL-4 cell DNA showed that the MMTV-related sequences were inserted into multiple locations of the EL-4 genome. Sequence analysis revealed that the MMTV-related cDNA clones included a part of the env gene and the right long terminal repeat of MMTV. However, the cDNA sequences were substantially different from published MMTV proviral sequences, most notably because of a contiguous deletion of 491 base pairs in the open reading frame within the U3 region.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D005786:Gene Expression Regulation / Q000187:drug effects; D005814:Genes, Viral; D008214:Lymphocytes / Q000502:physiology*; D008324:Mammary Tumor Virus, Mouse / Q000235:genetics*; D051379:Mice; D008815:Mice, Inbred Strains; D010704:Phorbols / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics; D013154:Spleen / Q000502:physiology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D010704:Phorbols; D012333:RNA, Messenger; D013755:Tetradecanoylphorbol Acetate