Fig. 6. APE1 colocalises with nuclear speckles and hOGG1 in UVA-irradiated cells. (A) NI and UVA-irradiated HeLa cells expressing APE1-YFP, were fixed 2 hours after irradiation and immunostained with SC35 antibodies. Arrows indicate the colocalisation between APE1 and SC35 in UVA-irradiated cells. (B) HeLa cells were co-transfected with plasmids expressing APE1-YFP and hOGG1-DsRed. Two hours after UVA irradiation, cells were fixed and directly visualised. Arrows indicate colocalisation between hOGG1-DsRed and APE1-YFP. (C) Mock (NI) or UVA-irradiated cells expressing hOGG1-GFP were collected 2 hours after irradiation and in vivo crosslinked with 50 µg/ml DSP. Proteins associated with the nuclear matrix were extracted and equivalent amounts were analyzed by western blot with antibodies against hOGG1, APE1 and Lamin A/C. Bars, 2 µm.