Kinetic signals from SMRT sequencing for the four epigenetic markers of cytosine 5mC, 5hmC, 5fC and 5caC. Synthetic oligonucleotides carrying two modified sites each (red bars) were subjected to SMRT sequencing and the polymerase kinetics compared by plotting the ratio of IPDs for each template position against a control template of identical sequence but lacking the modifications. The template is shown in the 5' to 3' direction from left to right, the polymerase movement is right to left across the template as indicated by the arrow. 5caC: 5-carboxylcytosine; 5fC: 5-formylcytosine; 5hmC: 5-hydroxymethylcytosine; 5mC: 5-methylcytosine; IPD: interpulse duration; SMRT: single-molecule: real-time.
Clark et al. BMC Biology 2013 11:4 doi:10.1186/1741-7007-11-4