Figure 4. Effect of NPM knockdown on DNA supercoil unwinding/rewinding after irradiation and/or heat shock.
(A) The halo assay was used to determine the effects of NPM knockdown on the ability of nuclear DNA to undergo supercoiling changes after irradiation with or without prior heat shock. The points are a mean of 4-5 experiments. (B) Excess halo diameter (EHD) values were calculated from the rewinding portion of the 4-5 individual experiments and averaged (bars) ± the SD. The only the non-transfected and the non-specific transfected showed a significant EHD reduction (p < 0.05, t-test) after heat shock. Inset: typical NPM levels. (C) EHD values for irradiated and heat plus irradiated HCC1806 cells. The non-transfected and the non-specific transfected cells showed a significant EHD reduction after heat shock.