. "At the beginning of this reaction, 1 molecule of 'Double-strand DNA containing an uracil opposite to a guanine at CpG sequences', and 1 molecule of 'MBD4 glycosylase' are present. At the end of this reaction, 1 molecule of 'MBD4 glycosylase:uracil complex' is present.

This reaction takes place in the 'nucleus'.
"^^ . . . . . "MBD4 glycosylase mediated recognition and binding of an uracil opposite to a guanine at CpG sequences"^^ . . . .