Folding of 140-base pair length DNA by a core of arginine-rich histones.

The nucleoprotein complex obtained by reconstitution of arginine-rich histones with 140-base pair length DNA has properties considerably closer to native core particles than the complex obtained with lysine-rich histones. A tetramer of arginine-rich histones folds 140-base pair length DNA into a particle (R body) with identical projections, on high resolution electron micrographs, as native core particles. The R body is more spherical in shape than the native nucleosome core particle. Both arginine- and lysine-rich histones contribute to the altered thermal stability and circular dichroism spectra of the core particle DNA.