FIG. 5.

Mutational analysis of the TRAP220 AB region. (A) Schematic representation of mutations introduced in the TRAP220 AB domain. The resulting constructs were FLAG tagged for generation of stable cell lines. (B) Silver staining of purified proteins and putative TRAP/Mediator complexes isolated from cell lines expressing various FLAG-tagged AB derivatives shown in panel A. Lane 1 contains a negative control (M2 agarose eluate from a control HeLa nuclear extract). Note that Δ1 and Δ2 polypeptides stain negatively with silver. (C) Immunoblotting with anti-FLAG antibodies to ascertain expression of selected AB mutants.