Davie J R, Delcuve G P
Department of Biochemistry, Faculty of Medicine, University of Manitoba, Winnipeg, Canada.
Biochem Cell Biol. 1988 Apr;66(4):256-61. doi: 10.1139/o88-034.
The distribution of 5-methylcytosine among H1-rich and -poor bovine thymus chromatin regions was determined. 5-Methylcytosine was enriched in H1-rich chromatin regions, with linker and nucleosomal DNA containing similar amounts of this modified base. Satellite I DNA sequences, which constitute 5-7% of the genome and are highly methylated, were preferentially localized among H1-rich chromatin regions, in accordance with the distribution of 5-methylcytosine. In contrast to the satellite I DNA sequences, prothrombin (a single copy DNA sequence) was localized among both H1-rich and -poor chromatin regions. The results of this study are consistent with the hypothesis that DNA methylation has a role in modulating the structure of chromatin.
测定了5-甲基胞嘧啶在富含H1和缺乏H1的牛胸腺染色质区域中的分布。5-甲基胞嘧啶在富含H1的染色质区域中富集，连接体DNA和核小体DNA中这种修饰碱基的含量相似。占基因组5-7%且高度甲基化的卫星I DNA序列，根据5-甲基胞嘧啶的分布情况，优先定位在富含H1的染色质区域中。与卫星I DNA序列相反，凝血酶原（一种单拷贝DNA序列）定位在富含H1和缺乏H1的染色质区域中。本研究结果与DNA甲基化在调节染色质结构中起作用这一假说一致。
