Figure 2

Enzyme titration and time course of purified telomere-specific nuclease that is a DNase. The triangles indicate increasing enzyme concentrations or time. (A) An enzyme titration of the purified telomeric nuclease (0, 0.95, 1.9, 4.75, 9.5, and 15.8 ng) is shown with substrates Ib and IVb. The reactions were incubated for 20 min. (B) Time course (0, 5, 10, 15, 20, and 30 min.) of purified telomeric nuclease at 4.75 ng per reaction with substrates Ia, Ib, IVa, and IVb is shown. (C) Cleavage of DNA but not RNA. Boxed sequences are non-telomeric ribonucleotides. Open gray circles are GGGGUU ribonucleotide repeat units, and open black circles are AACCCC ribonucleotide repeat units. Substrates (left to right) are Ib, M1:S18*, IVb, M2:S20*, S1:M3*, M1:M3*, S3:M4*, and M2:M4*.