Figure 4. Annexin A2 is required for homotypic Atg16+ vesicle fusion.

a, b, c, d) Analysis of Atg16L⁺/annexin A2⁺ vesicles fusion events at different Ca²⁺ concentration; Atg16L⁺/annexin A2⁺ vesicles were sorted with Alexa-488 or Texas-Red-conjugated antibody to obtained mixed color positive vesicles. In vitro fusion was analyzed at different Ca²⁺ concentrations. Single vesicles refer to structures as depicted in (b); double vesicles refer to structures as depicted in (c) and multiple fusion refers to structures as depicted in (d), mean and standard error were calculated from n>300 events. * p < 0.05; ** p < 0.01; **** p < 0.0001 e) Ultrastructural analysis of phagophore-like structures derived from the in vitro fusion of Atg16L⁺/annexin A2⁺ vesicles. f) Quantification of fusion events among Atg16L1 vesicles sorted from Anxa2^+/+ and Anxa2^−/− DCs; mean and standard error were calculated from n>300 events.. ** p < 0.01; *** p < 0.001 g, h) Quantification of fusion events among Atg-16L vesicles sorted from Anxa2^+/+ and Anxa2^−/− DCs, plus or minus reconstitution with annexin A2; mean and standard error were calculated from n>300 events. * p < 0.05; **** p < 0.0001 (all unpaired two-tailed Student’s t-test).