(F-H) NIH3T3 cells stably expressing empty vector (control) or mStrawberry‐Atg4BC74A (Atg4B mutant) were treated with 1000 μM LLOMe for 1 h. After LLOMe washout, cells were cultured in the presence or absence of both 10 μg/ml E64d and Pepstatin A, fixed at the indicated time points, and subjected to immunocytochemistry for Gal3 (green) and DAPI (blue) (F). The number of endogenous Gal3 puncta per control (G) or Atg4B‐mutant (H) cells was quantified by G‐Count. The data represent means±s.d. At least 50 cells were counted (n=3). Bars: 20 μm.Source data for this figure is available on the online supplementary information page. 