Figure 6.
Evoked neurotransmission is impaired in dSgip1 loss-of-function mutants
(A) Widefield images of FM 1-43 fluorescence at NMJs of control and dSgip1−/− larvae stimulated for 1 min with 90 mM KCl in the presence of 1.5 mM CaCl2. Scale bar: 5 μm. (A′) Quantification of FM 1-43 labeling intensity normalized to the NMJ area. 4 NMJs per animal were imaged from ≥5 animals per genotype. Statistical significance: unpaired t test. ns, not significant. Bars: mean ± SEM, and points are individual values.
(B and B′) Quantification of the amplitude (B) and frequency (B′) of mEJCs recorded in the presence of 1 mM CaCl2 at third-instar larval NMJs of the indicated genotypes to measure spontaneous neurotransmitter release. Number of animals recorded ≥ 11 per genotype. Statistical significance: unpaired t test. ns, not significant. Bars: mean ± SEM, and points are individual values.
(B″) Sample mEJC traces (quantified in B and B′).
(C and C′) Sample EJC traces (C) and quantification of the EJC amplitude (C′). EJCs were recorded at third-instar larval NMJs at 0.2 Hz stimulation in the presence of 1 mM CaCl2. Number of animals recorded ≥ 9 per genotype. Statistical significance: unpaired t test. ∗p < 0.05. Bars: mean ± SEM, and points are individual values.
(D and D′) Sample EJP traces (D) and quantification of relative EJP amplitudes (D′) of indicated genotypes. EJPs were recorded at third-instar larval NMJs for 600 s during a high-frequency stimulation train (10 Hz) in the presence of 2 mM CaCl2. Number of animals recorded ≥ 6 per genotype. Statistical significance: unpaired t test: not significant. Points: mean ± SEM.
(E and E′) Maximum projection confocal images of NMJs of third-instar larvae of the indicated genotypes labeled with antibodies against the glutamate receptor GluRIIA (E) and the quantification of the GluRIIA levels normalized to NMJ area (E′). Scale bar: 5 μm. (E′) Statistical significance: unpaired t test. ns, not significant. Bars: mean ± SEM, and points are individual values. See also Figure S3.