GCaMPs in C. elegans AWCon neuron in response to odor addition and removal. A, Schematic of AWC neuron location, and fluorescence micrograph of corresponding view. Scale bar, 10 μm. B, Omega bending frequency of wild-type C. elegans (N2) and 5A and 5G animals. C, Odor addition-evoked Ca2+ transients. Top, ΔF/F (%). Bottom, SNR. D, Odor removal-evoked Ca2+ transients. For both C and D, trial-averaged responses are colored red, blue, and cyan for GCaMP3, GCaMP5G, and 5A, respectively. Shaded area represents odor presence. Error traces indicate SEM.