Effects of CpG methylation on recognition of DNA by the tumour suppressor p53.
Effects of CpG methylation on recognition of DNA by the tumour suppressor p53.
复制标题
DOI：
10.1016/j.jmb.2008.11.054
复制
发表时间：
2009-02-13
影响因子：
5.6
通讯作者：
Veprintsev, Dmitry B.
中科院分区：
文献类型：
--
作者：
Petrovich, Miriana;Veprintsev, Dmitry B.
DNA的甲基化是控制基因组表达景观的机制之一。它的模式在癌症中改变，通常导致启动子区域的超甲基化和肿瘤抑制基因的异常表达。位于转录因子结合位点的CpG二核苷酸的甲基化可能通过阻止它们的结合或改变它们的特异性而有助于癌症的发展。我们研究了CpG甲基化对肿瘤抑制因子p53（一种参与致癌应激反应的转录因子）DNA识别的影响。p53识别大量DNA序列，其中许多含有CpG二核苷酸。我们系统地取代了CpG二核苷酸在每个位置的共识p53 DNA结合序列，并确定取代容忍的p53。我们通过荧光各向异性滴定比较了甲基化与非甲基化序列的结合亲和力。我们发现，在大多数情况下，p53的结合不受胞嘧啶甲基化的影响。然而，对于含有多个CpG二核苷酸的少数序列，例如RB和Met基因中的位点，甲基化导致p53结合增加4至6倍。该方法可用于定量CpG甲基化对其他DNA结合蛋白识别DNA的影响。
Methylation of DNA is one of the mechanisms controlling the expression landscape of the genome. Its pattern is altered in cancer and often results in the hypermethylation of the promoter regions and abnormal expression of tumour suppressor genes. Methylation of CpG dinucleotides located in the binding sites of transcription factors may contribute to the development of cancers by preventing their binding or altering their specificity. We studied the effects of CpG methylation on DNA recognition by the tumour suppressor p53, a transcription factor involved in the response to carcinogenic stress. p53 recognises a large number of DNA sequences, many of which contain CpG dinucleotides. We systematically substituted a CpG dinucleotide at each position in the consensus p53 DNA binding sequence and identified substitutions tolerated by p53. We compared the binding affinities of methylated versus non-methylated sequences by fluorescence anisotropy titration. We found that binding of p53 was not affected by cytosine methylation in a majority of cases. However, for a few sequences containing multiple CpG dinucleotides, such as sites in the RB and Met genes, methylation resulted in a four- to sixfold increase in binding of p53. This approach can be used to quantify the effects of CpG methylation on the DNA recognition by other DNA-binding proteins.
登录
查看更多内容
p53响应元素的序列分析表明p53四聚体与DNA靶标的多种结合模式。
影响因子：
14.9
作者：
Ma, Buyong;Pan, Yongping;Zheng, Jie;Levine, Arnold J;Nussinov, Ruth
通讯作者：
Nussinov, Ruth
影响因子：
64.5
作者：
Cawley, S;Bekiranov, S;Gingeras, TR
通讯作者：
Gingeras, TR
影响因子：
10.5
作者：
HOLLER, M;WESTIN, G;SCHAFFNER, W
通讯作者：
SCHAFFNER, W
影响因子：
4.8
作者：
Pomraning, Kyle R.;Smith, Kristina M.;Freitag, Michael
通讯作者：
Freitag, Michael
影响因子：
30.8
作者：
Futscher, BW;Oshiro, MM;Domann, FE
通讯作者：
Domann, FE