Fig. 6. PAM/Ab complexes and MPR/Ab complexes are internalized together.
After 10 min of uptake, MPR/Ab complexes had begun to collect in the TGN (A) and co-localized with PAM/Ab complexes in endosomes (A, right panel). After 20 min of PAM/Ab and MPR/Ab uptake, co-localization was observed in the TGN and in endosomes (B). Scale bars = 10 μm. The overlap in endosomes was partial, but more than 90% of the fluorescently labeled endosomes contained both cargos after 10 and 20 min (mean ± SE for 3 separate experiments). (C). When examined at the EM level using gold-tagged antibodies, multivesicular bodies representing 20 min of uptake of PAM and MPR antibodies generally contained both cargos; arrowheads mark ILVs that contained both cargoes (D). Arrow at left shows MPR/Ab complex in a tubule directed towards the Golgi complex (G). Scale bars = 200 nm.