Fig. 5: AVL and DVB synchronously fire propagating action potentials.

a, b Representative images showing synchronous GCaMP fluorescence in AVL and DVB. Time 0 is an arbitrary frame before neural activation. AVL soma (left panel, arrowhead), AVL axon (left and middle panels, arrow), preanal NMJs (right panel, arrow), DVB soma (right panel, arrowhead). Same scale bar for a, b. This imaging strain also has GCaMP expressed in DVC (marked by a red * in the right panel) which is irrelevant to DMP but used as a negative control. 13 imaging experiments were done with similar results. c Representative (normalized) calcium activities in AVL (red), DVB (blue), and DVC (black) soma. All activities normalized with maximum set to 1. Vertical line and markers: The timing of expulsion (green vertical line), the onset (asterisk), and the peak (circle) of AVL and DVB spikes. d Corresponding worm body length as a function of time. The blue curve is frame-by-frame and black is a smoothed version of the blue curve. (Smoothing used local regression to a second-order polynomial.) Red and blue asterisk/circle: same as in c. e Corresponding (normalized) intestinal calcium activities along the worm body axis (A: anterior, P: posterior). Curves (from left to right): the timing of the onset (white), the half-peak (black), and the peak (white) of calcium activities along the worm body axis. Vertical lines in d, e (from left to right): the earliest onset of intestinal calcium activity, the peak of pBoc, the onset of AVL, the peak of DVB, and the peak of aBoc. Source data are provided as a Source Data file.