Mirsaidov U, Timp W, Zou X, Dimitrov V, Schulten K, Feinberg A P, Timp G
Biophys J. 2009 Feb 18;96(4):L32-4. doi: 10.1016/j.bpj.2008.12.3760.
Methylation of cytosine is a covalent modification of DNA that can be used to silence genes, orchestrating a myriad of biological processes including cancer. We have discovered that a synthetic nanopore in a membrane comparable in thickness to a protein binding site can be used to detect methylation. We observe a voltage threshold for permeation of methylated DNA through a <2 nm diameter pore, which we attribute to the stretching transition; this can differ by >1 V/20 nm depending on the methylation level, but not the DNA sequence.
胞嘧啶甲基化是一种DNA的共价修饰，可用于使基因沉默，调控包括癌症在内的众多生物过程。我们发现，在厚度与蛋白质结合位点相当的膜中，一种合成纳米孔可用于检测甲基化。我们观察到甲基化DNA通过直径小于2纳米的孔渗透存在一个电压阈值，我们将其归因于拉伸转变；根据甲基化水平，该阈值每20纳米可能相差超过1伏，但与DNA序列无关。
