Representative ITC thermograms (upper) and isotherms (lower) for Pot1pN titrated with noncognate oligonucleotides in 50 mM Na2HPO4 at pH 7.5, 150 mM NaCl, and 1 mM BME at 20 °C. d(IGTTAC), 25 injections of 99 μM G1I titrated into 6 μM Pot1pN; d(GITTAC), 60 injections of 500 μM G2I titrated into 43 μM Pot1pN; d(GGUTAC), 25 injections of 144 μM T3dU titrated into 6 μM Pot1pN; and d(GGTUAC), 70 injections of 880 μM T4dU titrated into 43 μM Pot1pN.