A) Fluorescent measurement of PARP-1 zinc finger peptide with zinc or SIN-1. 100 μM PARP-1 zinc finger peptide was incubated with equal concentration of zinc or SIN-1 for 30 min at room temperature in 10 mM Tris buffer, pH=7.4. Emission scan was made from 300 to 400 nm with excitation at 280 nm. B) SIN-1 concentration dependence of fluorescent intensity at 340 nm. 100 μM PARP-1 zinc finger peptide was incubated with 10, 20, 50, 100 μM SIN-1, Samples were prepared and measured as described for panel A. *, p < 0.05 in student’s t-test vs. control group ([SIN-1] = 0), n = 3.