Figure 7. Soluble and Synaptic Vesicle-Targeted PA-BoNT Affect Locomotion Behavior in C. elegans after Photoactivation.

(A) Schematic of sPA- and vPA-BoNT constructs targeted to and activated at the synaptic vesicle membrane.

(B) Expression of sPA-BoNT fragments (top row) or vPA-BoNT fragments (bottom row) with GFP or mCherry tags as indicated. From left to right: transmitted light differential interference contrast (DIC), GFP, mCherry, and merged fluorescence. Shown are head (top) and body regions (bottom). Square arrows indicate fluorescence in nerve ring (top) and neuronal processes and synaptic boutons (bottom). Arrowheads indicate neuronal cell bodies. Scale bars, 50 μm.

(C) Left: mean ± SEM swimming cycles of WT (N2) or transgenic animals expressing soluble or synaptic vesicle (SV)-targeted variants of PA-BoNT, as indicated, without or with pulsed illumination (blue bars, 30 s every min for 60 min, 85 μW/mm²). n = 61–176 animals, assayed in n = 2-3 experiments, as indicated for each strain and condition. Right: mean ± SEM for statistical comparisons of baseline swimming cycles, measured prior to light exposure for all groups tested. Statistical analysis: unpaired t test with Bonferroni correction, ***p < 0.00025.

(D) Normalized data from (C), with data normalized to t = 0 time point.

(E) Group data of animals analyzed in (C) and (D) at the 75-min time point and after 24 h recovery in the dark. Statistical analysis: paired or unpaired t test with Bonferroni correction, *p < 0.0125, **p < 0.0025, ***p < 0.00025.