Identification and Molecular Cloning of Moloney Mouse Sarcoma Virus-Specific Sequences from Uninfected Mouse Cells

When uninfected mouse cell DNA is cleaved with restriction endonuclease EcoRI, a DNA fragment of 14.0 kilobases can be identified by hybridization to cloned DNA containing sarcoma specific sequences of Moloney mouse sarcoma virus (M-MSVsrc). The cellular DNA fragment contains the entire M-MSVsrcspecific sequences. The 14.0-kilobase EcoRI DNA fragment was cloned in bacteriophage λ . The sequence organization of a recombinant clone, λ · MTX-1, was analyzed by restriction endonuclease mapping, nuclease S1 mapping, and electron microscopy. The results indicate that λ · MTX-1contains an uninterrupted stretch of 1.0 kilobase similar to that found in the M-MSV genome.