Leptomycin B treatment causes nuclear accumulation of zyxin and results in co-localization of SIRT1 with zyxin. (A) COS-7 cells transfected with plasmids encoding HA-SIRT1 and GFP-zyxin were cultured for 24 h, in the presence or absence of 20 nM Leptomycin B during the last 6 h. Cells were stained with anti-Myc. Bars, 20 μm. (B) Confocal images show colocalization of SIRT1 and zyxin in nucleus in the presense of LMB. Bar, 10 μm. (C) Zyxin localization was classified in COS-7 cells expressing HA-SIRT1 and GFP-zyxin. "Cytoplasm" indicates COS-7 cell exhibiting GFP-zyxin only in the cytosol. "Nucleus" indicates COS-7 cell exhibiting nuclear-accumulated GFP-zyxin. Results (%) are the mean ± SD from three independent experiments.