Electrophysiological analysis demonstrates synaptic defects in <i>snpn-1</i> and <i>snt-1</i> mutants.

<p>(A,F) Representative evoked post-synaptic responses from voltage-clamped body wall muscles following nerve cord stimulation in acutely dissected worms in 5 mM Ca²⁺ (A) and 1 mM Ca²⁺ (B) extracellular saline. Plots of the mean ± SEM for evoked amplitude (B,G), evoked charge integral (C,H) evoked decay (D,I) and endogenous mini frequency (E,K) demonstrate that both <i>snpn-1</i> and <i>snt-1</i> mutants have release defects that are more severe in <i>snt-1</i> mutant. The significant synaptic defects of <i>snpn-1</i> mutants observed under low 1 mM Ca²⁺ conditions are fully rescued by expressing <i>SNPN-1</i> under the cholinergic neuronal <i>Punc-17</i> promoter(F-K). In all parameters plotted, <i>snpn-1;snt-1</i> double mutants do not exhibit additivity.