Distinct motor programs can be coupled to refine the repertoire of behavior dynamics.
However, mechanisms underlying such coupling are poorly understood. The defecation
motor program (DMP) of C. elegans is composed of a succession of body contraction and
expulsion steps, performed repeatedly with a period of 50–60 sec. We show that recurring
patterns of directed locomotion are executed in tandem with, co-reset and co-terminate with
the DMP cycle. Calcium waves in the intestine and proton signaling were shown to regulate …