Figure 3.
EDC crosslinking of RNA polymerase–ribosome complexes. (A) EDC crosslinking of RNA polymerase in the presence of the small ribosomal subunit (30S), large ribosomal subunit (50S), and ribosome (70S) with 30 mM and 250 mM KCl. (B) Normalized weighted spectral index of LC–MS/MS analysis of the Tris-glycine SDS-PAGE purified RNA polymerase–ribosome crosslink. (C) Venn diagram of crosslinked proteins after exposing a mixture of RNA polymerase and ribosomes to EDC and isolating the unique crosslinked species by 6–10% Tris-glycine (single band) and by 6–9% Tris-acetate SDS-PAGE (two bands). (D and E) Venn diagram of the proteins in the two species isolated from 6–9% Tris-acetate PAGE, which are specific to the EDC crosslinking of RNA polymerase in the presence of the small and the large ribosomal subunits.