Shlyaktenko, Luda; Woodcock, Chris (2010) CIL:7423, Homo sapiens, neuron. CIL. Dataset

The protein MeCP2 binds to symmetrically methylated CpG dinucleotides and is thought to transmit the (generally) repressive signals encoded in DNA methylation patterns. Mutations in MeCP2 lead to Rett syndrome. Here, MeCP2-DNA complexes have been imaged by AFM (Digital Instruments Nanoscope) in air using human MeCP2 and an 828 bp DNA sequence containing several methylated CpGs. MeCP2, which appears as bright circles in AFM images, and volume measurements of the complexes suggest that MeCP2 monomers and dimers are present and that MeCP2 binds DNA cooperatively. Other images in the linked set show looped structures and large complexes containing multiple DNA strands and MeCP2 molecules. These configurations are likely promoted by the multiple independent DNA-binding domains of MeCP2.

蛋白质MeCP2与对称甲基化的CpG二核苷酸结合，并被认为能够传递DNA甲基化模式中编码的（通常）抑制信号。MeCP2基因突变会导致雷特综合征。在本研究中，使用人源MeCP2和包含多个甲基化CpG的828碱基对DNA序列，通过原子力显微镜（Digital Instruments Nanoscope）在空气中对MeCP2-DNA复合物进行了成像。在原子力显微镜图像中，MeCP2呈现为明亮的圆形，复合物的体积测量结果表明MeCP2单体和二聚体的存在，以及MeCP2与DNA的协同结合。链接集中的其他图像展示了环状结构以及包含多个DNA链和MeCP2分子的大型复合物。这些构象可能是由MeCP2的多个独立DNA结合域所促进的。