C,D. Co-immunofluorescence staining of ER (CLIMP-63, green) and lysosomes (TMEM192-HA, red) in control and Sh-FAM134B U2OS cells over-expressing TFEB S142A:S211A-GFP (purple). BaFA1 was used at 100 nM for 4h. Scale bar 15 μm and 2 μm (higher magnification boxes) (C). In (D), Quantification of CLIMP63 fluorescence in TMEM192-HA decorated lysosomes. Mean +/- standard error of the mean (sem) of N=3 biological replicates. N= 21 (vehicle ctrl), N=33 (TFEB S142A:S211A-GFP ctrl), N=21 (vehicle shFAM134B), N= 30 (TFEB S142A:S211A-GFP shFAM134B) cells were analysed. Student's un-paired T-test ***p<0.0005; NS not significant. 