大鼠肝脏中含卫星DNA的染色质对核酸酶的敏感性随年龄增长而降低。

Nuclease susceptibility of the rat liver satellite DNA-containing chromatin decreases with age.

作者信息

Thakur M K, Chaurasia P

机构信息

Biochemistry and Molecular Biology Laboratory, Centre of Advanced Study in Zoology, Banaras Hindu University, Varanasi, India.

出版信息

Mol Cell Biochem. 1997 Jun;171(1-2):45-8. doi: 10.1023/a:1006850701989.

DOI:10.1023/a:1006850701989

PMID:9201694

Abstract

Nuclease susceptibility of the satellite DNA-containing chromatin of the liver of young (18 +/- 2 weeks) and old (100 +/- 5 weeks) rats was analysed using nick-translated rat 185 bp satellite I DNA fragment cloned in pBR322. With increasing concentration of DNaseI and micrococcal nuclease (MNase), multimeric forms of the satellite ladder gradually disappear in both the ages. The rate of disappearance is faster in young rats as compared to old ones. Such age-dependent decrease in the susceptibility of satellite DNA-containing chromatin reflects its condensation towards heterochromatization in old age.

摘要

使用克隆于pBR322的经缺口平移的大鼠185bp卫星I DNA片段，分析了年轻（18±2周）和年老（100±5周）大鼠肝脏中含卫星DNA的染色质对核酸酶的敏感性。随着脱氧核糖核酸酶I（DNaseI）和微球菌核酸酶（MNase）浓度的增加，两个年龄段的卫星梯状条带的多聚体形式逐渐消失。与年老大鼠相比，年轻大鼠中这种消失的速度更快。含卫星DNA的染色质敏感性的这种年龄依赖性降低反映了其在老年时向异染色质化的浓缩。