(A) Silver stained SDS-PAGE gels demonstrating co-immunoprecipitated proteins from F9 cell extract with normal IgG and Oct4 antibody under three different buffer conditions combined with two cross-linkers. Each lane contains proteins immunoprecipitated from 3×106 F9 cells. Arrows label bands that represent candidate Oct4-interacting proteins. These bands became prominent after cross-linking with DSP.
(B) Detection of immunoprecipitated Oct4 and co-immunoprecipitated Nanog by Western blotting. The lanes correspond to the lanes in Figure 1A, and each lane contains proteins immunoprecipitated from 3×106 cells. Arrows indicate bands of immunoprecipitated Oct4 for comparison of intensity. The input lane contains extract from 2.5×105 cells.