Abstract
The isolation of nuclear fraction from tobacco leaves and the extraction of histones from the isolated nuclei were investigated. A fairly pure nuclear fraction, freed from chloroplasts and other cellular organelles, was obtained by the combined method of differential centrifugation and density gradient centrifugation. Histones extracted by 0.25N HCl from isolated nuclei contained 2 main components as revealed by electrophoresis using cellulose acetate film (Separax). Tobacco nuclear histones seemed to be composed of small amount of arginine-rich histone and large amount of lysine-rich histone.