Analysis of Histones from Thymus of Young and Old Bovines by Gel Filtration

Abstract

Histones were prepared from thymus of young and old bovines and fractionated on a column of Sephadex G-75 (dextran gel filtration method). A distinct, fast-moving peak with a 275 m[mu]: 260 m[mu] ratio of 1.0 and very low arginine content appears to contain a complex of firmly bound histone-DNA (deoxyribonucleic acid). The size of this fraction appears to be increased in histones from old animals. The hypothesis that crosslinking of histones to DNA interferes with protein synthesis in organs from ageing animals is discussed in view of the present knowledge of histones as regulators of gene action.