Figure 5.

ERdj3 associates with unassembled Ig heavy chains along with BiP in a plasmacytoma cell line. Ag8(8) and Ag8.653 cells were incubated with (+) or without (-) DSP. Cells were lysed and 1/10 of each lysate was removed for direct blotting, whereas the remaining 9/10 of the lysate was incubated with protein A-Sepharose (PA) to isolate γ heavy chains and coprecipitating proteins. The precipitated protein complexes were reduced, separated by SDS-PAGE, and transferred for Western blotting with the indicated antisera. The Hsc70 signal served as a loading control.