A distributed set of interactions controls mu2 functionality in the role of AP-2 as a sorting adaptor in synaptic vesicle endocytosis - PubMed (original) (raw)

The rate of exocytosis and the size of recycling vesicle pool in μ2 mutant-expressing neurons. A, representative trace of exocytosis of vG-pH in μ2 mutant-expressing neurons. Neurons were triple-transfected with vG-pH, shRNA μ2, and rescue of each mutant and stimulated (1200 action potentials at 10 Hz) to trigger exocytosis of the entire recycling vesicle in the presence of bafilomycin (1 μ

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). YK, Y334A,K335A; KKKEEE, K341E/K343E/K345E. Error bars indicate S.E. B, the rate of exocytosis was determined from a single exponential fit. Time constants for exocytosis are not significantly different across the different mutants (WT, 42.3 ± 4.5 s, n = 12; Y_XX_ϕ, 45.5 ± 7.5 s, n = 14; T156A, 37.6 ± 5.0 s, n = 6; Y334A,K335A, 43.4 ± 7.2 s, n = 13; K341E/K343E/K345E, 45.3 ± 6.9 s, n = 12; 3M, 45.4 ± 11.2 s, n = 7; All-in-one, 42.0 ± 7.0 s, n = 5). C, the relative size of the recycling pool in transfected neurons was determined by measuring the maximum intensity of the change in vG-pH fluorescence during prolonged stimulation in the presence of bafilomycin. All cells were triple-transfected with same DNA mixture condition. Relative pool size to WT was determined as follows: Y_XX_ϕ, 92.2 ± 9.7%, n = 12; T156A, 94.1 ± 16.4 s, n = 12; Y334A,K335A, 90.2 ± 8.2 s, n = 12; K341E/K343E/K345E, 94.7 ± 9.9 s, n = 11; 3M, 81.9 ± 15.5 s, n = 6; All-in-one, 71.9 ± 11.1 s, n = 8) *, p <0.05. The solid line indicates the SV recycling pool of AP-2KD (12).