AP complexes are dispensable for cargo sorting into Golgi-derived tubular carriers. (a) Schematic representation of AP-1, AP-2, AP-3, and AP-4. (b) Confirmation of KO by immunoblot analysis of endogenous targets. Notice that AP-2 μ2 KO is not complete. Cells with complete KO of AP-2 μ2 were not found in the screening. WB, Western blotting. (c) Images from spinning-disk, live-cell microscopy of LAMP1 or TfR reporter proteins in AP-KO cell lines at the indicated times after biotin addition. Tubular carriers containing LAMP1 or TfR reporters were found in all of the AP-KO cells. Bars: 10 µm; (insets) 1 μm. (d) The LAMP1 reporter protein was expressed in each AP-KO cell line. Cells were fixed 60 min after the addition of biotin and stained for an endogenous lysosomal marker (LAMTOR4) to assess the requirement of AP complexes for transport to lysosomes. Bars: 5 µm; (insets) 1 µm.