Fig. 4

Terminal deoxynucleotidyl transferase (TdT) treatment of samples pretreated with different enzymes. H4 DNA mixture containing 25 fmol of FAM-labeled DNA was subjected to different enzymatic treatments, followed by TdT treatment. The panels show the samples before treatment (a, identical to that shown in Fig. 1a); samples treated with TdT alone (b); samples treated with SAP followed by TdT (c); samples treated serially with SAP, T4DP, and TdT (d); samples treated serially with a combination of exonuclease III and T4DP, T4DP alone, and TdT (e). Between the two enzymatic treatments, the samples were purified using the DNA clean-up column. Following the TdT treatment, the samples were purified using a DNA clean-up column before mixing with HiDi-LIZ500. All data were y-axis scaled so that sums of FAM peak areas are apparently even across the panels. Two calibrator peaks from the LIZ size standard (100 and 300 nucleotides) are indicated by filled triangles, and relevant size marker locations are also indicated