Santoro R, D'Erme M, Mastrantonio S, Reale A, Marenzi S, Saluz H P, Strom R, Caiafa P
Department of Biochemical Sciences A. Rossi Fanelli, University of Rome La Sapienza, Italy.
Biochem J. 1995 Feb 1;305 ( Pt 3)(Pt 3):739-44. doi: 10.1042/bj3050739.
Within the H1 histone family, only some fractions enriched in the H1e-c variants are effective in causing a marked inhibition, in vitro, of enzymic DNA methylation and, in gel retardation and Southwestern blot experiments, in binding double-stranded (ds) CpG-rich oligonucleotides. Both the 6-CpG ds-oligonucleotide and the DNA purified from chromatin fractions enriched in 'CpG islands' are good competitors for the binding of H1e-c to 6-meCpG ds-oligonucleotide. Because of their ability to bind any DNA sequence and to suppress the enzymic methylation in any sequence containing CpG dinucleotides, these particular H1 variants could play some role in maintaining linker DNA at low methylation levels and even in preserving the unmethylated state of the CpG-rich islands which characterize the promoter regions of housekeeping genes.
在H1组蛋白家族中，只有一些富含H1e - c变体的组分在体外能有效显著抑制酶促DNA甲基化，并且在凝胶阻滞和蛋白质印迹实验中能与富含双链（ds）CpG的寡核苷酸结合。6 - CpG双链寡核苷酸以及从富含“CpG岛”的染色质组分中纯化的DNA都是H1e - c与6 - meCpG双链寡核苷酸结合的良好竞争者。由于这些特定的H1变体能够结合任何DNA序列并抑制任何含有CpG二核苷酸序列中的酶促甲基化，它们可能在将连接DNA维持在低甲基化水平甚至在保持管家基因启动子区域特征性的富含CpG岛的未甲基化状态方面发挥一定作用。
