Fig. 4: Reduced MSL-7 effects in Tfeb-KO or Tfe3-KO cells in vitro.

a Tfeb-KO or Tfe3-KO INS-1 cells were treated with MSL-7 for 4 h, and immunostained using anti-TFEB (left) or anti-TFE3 antibody (right). After DAPI staining, cells were subjected to confocal microscopy. b Tfeb-KO or Tfe3-KO INS-1 cells transfected with mRFP-GFP-LC3 tandem construct were treated with MSL-7 for 16 h, and the numbers of autophagosome and autophagolysosome were counted (F = 178.7, df treatment = 5, df residual = 114) (right). Representative pictures are presented (left). Inset images were magnified to show red (autophagolysosomes), green, and yellow (autophagosomes) puncta. c Tfeb-KO or Tfe3-KO INS-1 cells transfected with prepro-mIAPP-HA or prepro-hIAPP-HA were treated with MSL-7 for 16 h. Immunoblot analysis was conducted (F = 32.9, df treatment = 5, df residual = 12) (left). Densitometric value of HA bands normalized to the respective vehicle-treated cells (−) are presented (right). d Tfeb-KO (left) or Tfe3-KO (right) INS-1 cells transfected with prepro-mIAPP-HA or prepro-hIAPP-HA were treated with MSL-7 for 16 h without 3-MA, and apoptosis was measured (F = 5.8, df treatment = 11, df residual = 36 in left panel; F = 11.3, df treatment = 11, df residual = 36 in right panel). e Tfeb-KO or Tfe3-KO INS-1 cells transfected with prepro-mIAPP-HA or prepro-hIAPP-HA were treated with MSL-7 for 16 h in the presence of 3-MA, and apoptosis was measured (F = 24.1, df treatment = 11, df residual = 36). All data in this figure are the means ± SEM from more than 3 independent experiments performed in triplicate. (scale bar, 5 μm) *P < 0.05; **P < 0.01; ***P < 0.001 by one-way ANOVA with Tukey’s test. (n.s. not significant) Source data are provided as a Source Data file.