Nhp6 and Hmo1 stimulate targeting of the SWI/SNF complex mediated by Gal4-VP16. EMSA analyses comparing the effect of different concentrations of each HMG protein on Gal4-VP16-mediated recruitment of SWI/SNF to a mononucleosome probe. A 216 bp DNA segment containing a single Gal4 binding site and the 601 nucleosome positioning sequence was reconstituted into a mononucleosome. The resulting probe contains the Gal4 binding site in the extranucleosomal DNA region, as depicted in figure A. After binding incubations, the samples were analyzed by electrophoresis in non-denaturing polyacrylamide gels (3.5%, AA:Bis 60:1). Migration of naked DNA, mononucleosome, and the different complexes is indicated at right of the pictures. Migration of the mononucleosome is indicated schematically. The components of each reaction are depicted on top of the pictures. Pictures in figures B and C are representative of three independent assays performed for each set of HMG proteins. These proteins may also be present in the Gal4-VP16/SWI-SNF/Nuc complex, which cannot be confirmed or discarded through this analysis. A) Schematic representation of the probe used in the assays. B) EMSA analysis for Nhp6A and Nhp6B proteins. C) EMSA analysis for Hmo1 and HMGB1 proteins.