Isolation and Characterization of the Nuclear Matrix from Rat Liver Nuclei

Abstract

Two procedures to isolate the nuclear matrix from rat liver nuclei were developed. These prevent contamination by nuclear membrane fragments and consist of (A) three consecutive treatments with 1 % Triton X-100 buffer, DNase I digestion and high salt extraction; and (B) a modification of Berezney's method in that isolated nuclei were washed three times with 1 % Triton X-100 buffer in the first step. The nuclear matrices obtained from rat liver nuclei by these procedures consist largely of protein (88.3-88.6 %) with small amounts of RNA (6.5-10.6%), DNA (0.9-4.6%) and phospholipid (0.2-1.2%). Sodium dodecyl sulfate-acrylamide gel electrophoresis of the nuclear matrix proteins gives three major polypeptides with molecular weights of 60, 000-80, 000.