E,F. Co-immunofluorescence staining of ER (CLIMP-63, green) and lysosomes (Lamp1, red) in WT and Fam134bKO MEF 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) (E). In (F), Quantification of CLIMP63 fluorescence in Lamp1 decorated lysosomes. Mean +/- standard error of the mean (sem) of N=3 biological replicates. N= 20 (vehicle ctrl), N=22 (TFEB S142A:S211A-GFP ctrl), N=21 (vehicle Fam134bKO), N= 20 (TFEB S142A:S211A-GFP Fam134bKO) cells were analysed. Student's un-paired T-test ***p<0.0005; NS not significant. 