FIG. 4.

Analysis of interaction between expressed N protein and M protein. (A) DBT cells that were infected with SinN pseudovirions (lanes 1 and 2) or SinM pseudovirions (lanes 3 and 4) were labeled with Tran[³⁵S] label from 5 to 5.5 h p.i. The intracellular proteins were immunoprecipitated with an anti-N protein monoclonal antibody (lanes 1 and 4) or an anti-M protein monoclonal antibody (lanes 2 and 3), and viral proteins were analyzed by SDS–15% PAGE. (B) Equal volumes of ³⁵S-labeled intracellular protein lysates from DBT cells, infected with SinM pseudovirions alone and SinN pseudovirions alone, were mixed, and intracellular proteins were immunoprecipitated with an anti-N protein monoclonal antibody (lane 1), an anti-M protein monoclonal antibody (lane 2), or an anti-H2K monoclonal antibody (lane 3). The viral proteins were analyzed by SDS–12% PAGE. (C) DBT cells were coinfected with SinM pseudovirions and SinN pseudovirions, and intracellular proteins were labeled with Tran[³⁵S] label from 5 to 5.5 h p.i. The intracellular proteins were immunoprecipitated with an anti-N protein monoclonal antibody (lane 1), an anti-M protein monoclonal antibody (lane 2), or an anti-H2K monoclonal antibody (lane 3). Viral proteins were analyzed by SDS–15% PAGE. The marked protein bands (indicated by arrows and an asterisk) are non-MHV proteins.