Conformation of the HMG17-nucleosome complex.
The nucleosome core binds more than two molecules of HMG17 at low ionic strength (8.9 mM Tris-HCl/8.9 mM boric acid/0.25 mM Na2EDTA, pH 8.3). Circular dichroism of the complexes showed only minor conformational changes of the nucleosome core DNA on binding of HMG17, with no detectable change in the histone secondary structure. The fluorescence of N-(3-pyrene) maleimide bound to -SH groups at Cys-110 of H3 histones in the core particle suggested that the structure of the histone octamer assembly changed little upon binding of HMG17 to the nucleosome. These observations support the idea that even a high level of HMG17 binding, e.g., four HMGs per nucleosome, alone, does not open up the core particle.
D000818:Animals; D002417:Cattle; D002942:Circular Dichroism; D004591:Electrophoresis, Polyacrylamide Gel; D006609:High Mobility Group Proteins / Q000032:analysis*; D009707:Nucleosomes / Q000032:analysis*; D009994:Osmolar Concentration; D011487:Protein Conformation; D013050:Spectrometry, Fluorescence
D006609:High Mobility Group Proteins; D009707:Nucleosomes