Fig. 1. Laser irradiation systems and accumulation of WRN. (A) Laser irradiation systems. The left column shows the 365 nm pulse laser irradiation system, producing the lower dose and the higher dose irradiation, which are regulated by the filter in front of the mirror. The right column shows the 405 nm laser system. (B) Three types of damage induced by 365 nm and 405 nm laser irradiation. HeLa cells irradiated with the lower dose or the higher dose of 365 nm laser, or with 405 nm laser of different scan times, were stained with anti-poly(ADP)ribose (left, for single-strand breaks) or by H2AX antibody (middle, for double-strand breaks), respectively, or accumulation of GFP-tagged OGG1 at irradiated sites (right, for base damage) is shown. The amounts of accumulated molecules for poly(ADP)ribose, H2AX and GFP-OGG1 after lower and higher dose irradiation with the 365 nm or 405 nm laser were quantified in the graphs. (C) Time-dependent accumulation of GFP-tagged WRN after higher dose irradiation with the 365 nm laser in HeLa cells. (D) Accumulation of GFP-tagged XRCC1 and LIGIII (upper panels) and no accumulation of GFP-tagged WRN (lower panels) after lower dose irradiation with the 365 nm laser in HeLa cells. Arrows indicate the sites of irradiation.