UHRF1 (also known as Np95) preferentially binds hemimethylated CG dinucleotides in DNA via its SRA domain (Avvakumov et al. 2008, Qian et al. 2008, and inferred from the mouse homolog). The UHRF1-bound unmethylated cytosine base is flipped out of the DNA helix and into a pocket of UHRF1 (Avvakumov et al. 2008). UHRF1 also binds dimethylated and trimethylated lysine-9 of histone H3 through its tandem Tudor domain (Nady et al. 2011, Rothbart et al. 2012, Rothbart et al. 2013, Cheng et al. 2013) and unmethylated histone H3 through its PHD domain (Hu et al. 2011, Wang et al. 2011, Rajakumara et al. 2011, Cheng et al. 2013).