Related to Fig. 1 . RTN3L and SEC24C are needed for the delivery of RTN4 fragments to lysosomes during basal autophagy. siCtrl, siRTN3L, siSEC24C, and siCALCOCO1 cells were treated for 6 h with Baf or Baf + MRT68921. The ER-phagy receptor, CALCOCO1, was used as a control for basal autophagy in this experiment. Top, representative images for the data quantitated below. Arrowheads mark RTN4 fragments delivered to lysosomes. Bottom, the relative pixel intensity for each condition is the mean intensity of RTN4-GFP in the pixels that overlap with LAMP1-mCherry. The control for each condition was without Baf (DMSO only) and set to 1.0. MRT68921 was used to block autophagosome maturation. Error bars represent SEM, n = 3 independent experiments. The results were quantified from 36 to 66 cells. NS: not significant (P ≥ 0.05), * (P < 0.05), **(P < 0.01), Student’s unpaired t test.