Fig. 3

Tyraminergic RIM neurons are activated during backward locomotion. a 3D reconstructed fluorescent image of the head region of a jqIs75;jqEx516 worm. RIM (orange), RIC (pink), and RME (green) are shown. Cell bodies are indicated by asterisks. Dashed lines denote the pharynx. Graticule size is 5 μm. b G-CaMP images and the corresponding transmitted-light images of a transgenic animal (jqIs73;jqIs75) expressing G-CaMP7 in RIM and RME. Scale bar represents 10 μm. c Representative calcium trace of RIM. The light-gray line shows raw data of ratio (R: G-CaMP7 / DsRed), and the black line shows the moving average of R across a 0.27 s window. Periods of forward and backward locomotion are indicated by the green and red bars, respectively. d Quantitative analysis of the fluorescence ratio changes of RIM (n = 9 from six animals). **P < 0.01, Student’s two-tailed t-test. Error bars, SEM. e Calcium dynamics of RIM (red) and RME (blue) recorded from an animal. Light colored lines show normalized raw data, and dark colored lines show moving averages across a 0.27 s window. RIM and RME show reciprocal calcium transients in the directional switch from forward (green bar) to backward (red bar) locomotion. f Cross-correlation analysis of calcium dynamics between RIM and RME. Gray lines are individual data (n = 8), and the black line shows a mean trace