Figure 3.

Disruption of FRET between the receptor, Ca_V2.2 channel, and Gβγ at hippocampal boutons of 1a^−/− neurons. A, Confocal images of axonal part of 1a^−/− hippocampal pyramidal neuron that was cotransfected with Ca_V2.2^CFP and Gβ₁^YFP. Scale bar, 2 μm. B, Lack of specific FRET between Ca_V2.2^CFP and Gβ₁^N′-YFP in 1a^−/− boutons: under miniature synaptic activity (Cnt, n = 31, N = 6), in the presence of 10 μm baclofen (n = 16, N = 4), and in TeTx-treated (n = 14, N = 3) and young (n = 14, N = 4) neurons. Transfection of 1a^−/− neurons with GB_1a resulted in rescue of Ca_V2.2^CFP/Gβ₁^N′-YFP FRET (n = 17, N = 4, ***p < 0.0001). C, Lack of specific FRET between Ca_V2.2^CFP and either Gγ₂^N′-YFP (n = 10, N = 3) or Gγ₂^C′-YFP (n = 9, N = 3). D, Disruption of specific FRET between Ca_V2.2^CFP and GB₂^YFP protein in 1a^−/− neurons (n = 8, N = 3, ***p < 0.0001). E, Diagram illustrating disruption of Ca_V2.2^CFP/Gβ₁^YFP FRET in boutons of 1a^−/− neurons. One-way ANOVA analysis with post hoc Bonferroni's multiple comparison tests (B) and paired t test (C, D) indicated significance. Error bars indicate SEM.