In vitro Cleavage of Pr65gag by the Moloney Murine Leukaemia Virus Proteolytic Activity Yields p30 whose NH2-Terminal Sequence Is Identical to Virion p30

In vitro cleavage of Gazdar murine sarcoma virus Pr65^gag, which has all of the antigenic determinants of Moloney murine leukaemia virus Pr65^gag, i.e. p15, p12, p30 and p10, by the Moloney murine leukaemia virus proteolytic activity yielded a p30 whose partial NH₂-terminal sequence was identical to Moloney murine leukaemia virus. Both [³H]leucine-labelled and unlabelled Pr65^gag were used to generate the cleaved p30.