从小鼠大脑中分离卫星DNA染色质和主带DNA染色质。

Separation of satellite DNA chromatin and main band DNA chromatin from mouse brain.

作者信息

Mazrimas J A, Balhorn R, Hatch F T

出版信息

Nucleic Acids Res. 1979 Oct 25;7(4):935-46. doi: 10.1093/nar/7.4.935.

DOI:10.1093/nar/7.4.935

PMID:116196

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC342272/

Abstract

Using restriction endonucleases which preferentially digest mouse main band DNA and leave satellite DNA intact, we have isolated highly purified chromatin fractions containing only mouse satellite or main band DNA. Following the digestion of mouse brain nuclei with EndoR Alu I, main band DNA chromatin is selectively extracted with 10mM Tris, 10mM EDTA. Satellite DNA chromatin is subsequently extracted from the nuclear pellet with Tris-3M urea and further purified on sucrose gradients. Chromatin extracted from digested nuclei with Tris-EDTA contains only main band DNA and has a molecular weight lower than 2 x 10(6). Chromatin fractions obtained from the lower regions of sucrose gradients of the Tris-Urea extracts contain 40--95% satellite DNA and have a molecular weight of 6 to 8 x 10(6). Both the satellite DNA and main band DNA chromatins contain all five histones and have a protein to DNA ratio of 1.3 to 1.

摘要

使用优先消化小鼠主带DNA并使卫星DNA保持完整的限制性内切酶，我们已分离出仅含有小鼠卫星DNA或主带DNA的高度纯化的染色质组分。用内切酶Alu I消化小鼠脑细胞核后，用10mM Tris、10mM EDTA选择性提取主带DNA染色质。随后用Tris-3M尿素从核沉淀中提取卫星DNA染色质，并在蔗糖梯度上进一步纯化。用Tris-EDTA从消化的细胞核中提取的染色质仅含有主带DNA，分子量低于2×10⁶。从Tris-尿素提取物的蔗糖梯度较低区域获得的染色质组分含有40%-95%的卫星DNA，分子量为6至8×10⁶。卫星DNA和主带DNA染色质均含有所有五种组蛋白，蛋白质与DNA的比例为1.3比1。