Generation of a uniform 3' end RNA of murine leukemia virus.

Using the S1 nuclease mapping technique, we demonstrated that the majority of Moloney murine leukemia RNA molecules, isolated either from the nucleus or cytoplasm of infected mouse cells, share a uniform 3' end located at the border of the R and U-5 regions of the long terminal repeat. When the long terminal repeat sequences were inserted in the pSV plasmid downstream of the simian virus 40 late promoter, the 3' end of the viral RNA was also generated close to the R region of the long terminal repeat. These results demonstrate that the long terminal repeat signals the generation of an authentic 3' end when situated downstream of an actively transcribed region.