The authors regret that there is an typographical error in the DNA sequence shown in Fig. 1b and the graphical abstract of this paper: The G and C bases of the right-hand tetraloop as drawn (positions 32 and 35) should be transposed; the correct sequence of this loop is ‑C32-T33-T34-G35-. Please note that the sequences shown in Supplementary Table 3 do not suffer this error, and are correct.
Also, in Table 1 of the main paper the average atomic rms deviation from the average structure for the backbone atoms (N, Ca, C) of PARP-1 finger 1 (residues 7-93) should be 0.48 ± 0.11Å (rather than 0.50 ± 0.12Å).
The corrected Fig. 1 and Graphical Abstract appear on next page.


