Splice acceptor site for the env message of Moloney murine leukemia virus.

We report the isolation and sequence of a cDNA clone containing part of the env message of the Moloney murine leukemia virus (MoMuLV). This clone was derived from a rat thymic lymphoma induced by MoMuLV. The AG acceptor site employed in this message is located at position 5490 in the MoMuLV genome. This splice site is detectable at the cDNA level by the creation of a novel SacI restriction site not present in the viral genome. In the -1 to -40 region, this AG acceptor site is preceded by four conserved heptanucleotides (PyXPyTPuAPy) that may function as acceptors for removal of the 5' end of the intron.