Isolation and Characterization of Total Histones from Chicken Erythrocytes: A Simpler Method Using Detergent

Abstract

Histones are highly conserved small basic proteins that are positively charged at neutral pH. They associate with the DNA to form a polymer called chromatin. Many studies have focused on the isolation of histones from tissues and cell lines. The present study reports the isolation of good-quality histones from chicken erythrocytes by using a high-speed centrifugation method through a sucrose gradient. The method described in the present study is simpler and is a deviation from the usual requirement of an ultracentrifugation step for the purification of the histones. The isolated histones were quantified using spectrometric methods and the quality and integrity of the histones were evaluated by a high-resolution SDS 18% PAGE. The isolated histones were found to be homogeneously pure. They contained all the histone subtypes in stoichiometric amounts along with the histone variants. The isolated total histones were subsequently used for routine histone protease assays and they were demonstrated to be a great substrate for these assays. The present study thus describes the chicken erythrocyte total histones isolated from chicken blood (a waste product of the slaughterhouse), by a high-speed centrifugation method, evaluation of their quality and their usefulness as a substrate for histone-specific protease assays.