Fig. 4

Difopein enhances both ER and cell-surface expression of Eag1. Representative confocal micrographs showing the effect of R18 mutant and difopein co-expression on Eag1 immunofluorescent signals in HEK293T cells, in the absence (A) or presence of 12-h treatment with 10 μM MG132 (B) or 100 μM chloroquine (CQ) (C). Eag1 was detected with the anti-Eag1 antibody (cyan), nuclei were counterstained with DAPI (blue), and YFP-tagged proteins were directly visualized (green). ER and cell-surface localizations of Eag1 were determined by co-localization with the ER marker calnexin (red; left panels) and the plasma membrane marker cadherin (red; right panels), respectively. Merged images are shown in the third column of each panel. Arrows indicate intracellular ER staining, whereas arrowheads denote plasma membrane staining. Scale bar, 10 μm. Data shown here are representative of over 80 cells from at least three independent experiments. See Additional file 1: Fig. S3 for further quantitative analyses