Fig. 3: UNI418 negatively affects autophagosome-lysosome fusion and endosome acidification.
From: A dual inhibitor of PIP5K1C and PIKfyve prevents SARS-CoV-2 entry into cells
a Live-cell imaging of HEK293T cells stably expressing mCherry-GFP-LC3 treated with 0.5 μM UNI418 at the indicated time points; the images within the white rectangular boxes are magnified on the right side. Scale bar, 30 µm. The number (b) and area (c) of GFP-positive dots per cell were quantified by ImageXpress. d Immunofluorescence images illustrating the inhibition of endolysosomal acidification by UNI418. Vero cells were treated with the mock control or 1 µM UNC3230, apilimod or UNI418 for 1 h at 37 °C. Acridine orange (4 µg/mL) was added to the compound-treated live cells, followed by additional incubation for 30 min. The cells were analyzed by confocal microscopy using two emission wavelengths at 493–560 (green) and 590–720 nm (red) after excitation at 488 nm. Merged images are presented, and images within the white rectangular boxes are magnified on the right side. Original magnification, 630×. The green-to-red fluorescence intensity ratio (e) and the area of fluorescent spots (f) were quantified. b, c, e, f The data are presented as the means ± SEMs, with a minimum of 200 spots. Statistical significance was determined by Student’s t test; *p < 0.05, **p < 0.01, ***p < 0.001 and ****p < 0.0001. n.s., not significant.
