Pharyngeal recordings from wild-type andrab-3 mutants. Characteristic recordings of a (A, D) wild-type worm,rab-3(js49) (B, E), andrab-3(y250) (C) mutants.Arrows indicate the MC-induced transients, and thecircles indicate M3-induced transients. In wild-type animals (D), MC activity that failed to initiate a pharyngeal pump was characteristically observed as a single transient. However, in rab-3 mutants (E), MC activity that failed to initiate a pharyngeal pump was nonsynchronous, typically consisting of a small burst of transients spaced in a 50–100 msec interval. All traces are mV versus time.