Association of moloney murine leukaemia virus proteins: an assay for hydrophobic protein-protein interactions.

Protein-protein interaction of Moloney murine leukaemia virus was studied by an assay where one protein preparation was coupled covalently to Sepharose, and binding of radiolabelled proteins to the protein-Sepharose was examined. It was found that the virus proteins gp70, p30, p15E and p15 in solution could associate weakly to disrupted virus particles and to p30. However, when the disrupted virus particles and p30 were coupled to Sepharose in the presence of Triton X-100, stronger binding of the four proteins was observed. Only low or no binding of p12 and p10 was observed to these protein-Sepharoses. The results are discussed with respect to the assembly and structure of the virus particle.