CTCF distribution around AsisI sites in IDHwt and IDHR132H DIvA cells. CTCF distribution around AsisI sites in IDHwt and IDHR132H DIvA cells

IDH1 mutation impacts CTCF binding and function through methylating cytosine in the CTCF binding motif. We hypothesize that the impairment of CTCF-associated DNA repair process may be relevant to the loss of CTCF chromatin association and shifts in chromatin conformation. Chromatin immunoprecipitation-sequencing confirmed the loss of CTCF coverage in the proximity sites of AsisI sites in IDH1 mutant cells. Overall design: ChIP-seq for CTCF was performed in IDH1 wild-type and mutant DIvA cells with or without 4OHT treatment. 4C-seq with two DSB sites was performed in IDH1 wild-type and mutant DIvA cells with or without 4OHT treatment.

异柠檬酸脱氢酶1（IDH1）突变通过在CCCTC结合因子（CTCF）结合基序内使胞嘧啶甲基化，进而影响CTCF的结合活性与功能。我们提出如下假说：与CTCF相关的DNA修复过程受损，可能与CTCF的染色质结合能力丧失以及染色质构象改变存在关联。染色质免疫共沉淀测序（ChIP-seq）证实，在IDH1突变细胞中，AsisI位点邻近区域的CTCF覆盖度出现丢失。总体实验设计：针对CTCF的ChIP-seq实验在IDH1野生型与突变型DIvA细胞中开展，两组细胞均分别施加或不施加4OHT处理；针对两个DNA双链断裂（DSB）位点的4C-seq实验，同样在上述分组的细胞中完成。