Fig. 2

The interaction between hTopBP1 and hMYH increases following HU treatment. a HEK293 cells were incubated with 20 mM HU for 1 or 3 h and then immunoprecipitated with anti-hTopBP1 antibodies. The precipitated proteins were detected using anti-hMYH and anti-hTopBP1 antibodies. β-Actin was used as a loading control. b Protein expression levels and their interaction were quantified and are presented as mean ± standard error (of three independent experiments). P values were calculated using a paired t test. *p < 0.05, **p < 0.01 compared to the Control (HU-untreated cells). c Cells were seeded and grown on coverglass bottom dishes. After 24 h, cells were either untreated or treated with various concentrations of HU for 1 h, fixed with 4 % paraformaldehyde, and permeabilized with 0.1 % Triton X-100 in PBS. Cells were subsequently incubated with anti-hMYH and anti-hTopBP1 antibodies and then stained with Alexa Fluor^® 488 (hMYH/Green), Cy3 (hTopBP1/Orange), and To-pro^®-3 (nucleus/Red). Scale bar 10 μm