Methyl-CpG binding protein 2 (MeCP2) is a protein associated with transcriptional repression of other proteins and its various mutants are found in Rett syndrome patients, which is a severe neurodevelopmental disease found in 1/15,000 females. It has specific binding affinity to methyl-CpG domain but also bind to architectural DNA structure. Here, its binding dynamics to Holliday junction structure was investigated by using single molecular detections; scanning confocal fluorescence microscope and wide-field evanescent field fluorescence microscope. Through these studies, we could distinguish the difference of transitions of the substrate with and without MeCP2. The effect of this MeCP2 binding to 4WJ will be discussed in terms of the structures and transition times
