Fig. 6.

GLR-5 induces IP₃-dependent Ca²⁺ release from intracellular Ca²⁺ store and triggers neuropeptide release. a, b AIB calcium dynamics induced by 5 mM quinine pre-treated with or without Thapsigargin (TG, treated for 3 min.) in freely behaving worms acquired by the iCaN system. Wild-type (WT), glr-1, glr-5, and itr-1 mutant worms were tested. Traces are synchronized according to the time of quinine application (dash lines). a Heat maps; b peak calcium changes, and c FHWMs for AIB calcium dynamics. Error bars: s.e.m.. n ≥ 14. ***p < 0.001 (t test). N.S. represents no significant difference. d, e Quinine-induced feeding suppression (d), but not reversals (e), was dramatically defective in egl-8, plc-3, itr-1, and unc-31 mutant worms. Error bars: s.e.m.. Reversal index, n = 6 groups, 10 worms/group at least; Pumping rate, n = 16 worms. ***p < 0.001 (t test). e Optogenetic stimulation of AIB inhibited pumping rate in eat-4 mutant worms, but not in unc-31 mutant worms. Worms-expressing ChR2 specifically in AIB were tested. The transgenic animals cultured on ATR-free plates were taken as control. Error bars: s.e.m. n ≥ 12. ***p < 0.001 (Wilcoxon test). g Optogenetic stimulation of AIB inhibited pumping rate in glr-1 mutant worms, but not in glr-1;unc-31 mutant worms. Worms expressing ChR2 specifically in AIB were tested. The transgenic animals cultured on ATR-free plates were taken as control. Error bars: s.e.m. n ≥ 12. ***p < 0.001 (Wilcoxon test)