Skip to main content
. 2021 Feb 18;12:1115. doi: 10.1038/s41467-021-21388-w

Fig. 5. MBON-γ2α′1 activation of PAM-β′2a encodes shock omission during reversal learning.

Fig. 5

a Schematic of MBON-γ2α′1, MBON-β′2mp, and empty-splitGAL4 driver lines. b Activating MBON-γ2α′1 during CS+ reversal with the highest light dose enhances CS+ reversal, while activating MBON-β′2mp with the lowest dose impairs CS+ reversal. n = 12,8,7; 11,10,12; 12,9,7 independent groups of flies. Statistical comparison is by one-way ANOVA, with Dunnett’s multiple comparisons test against empty-splitGAL4 control. c Silencing MBON-γ2α′1 during CS+ reversal at the lowest light dose impairs CS+ reversal, while silencing MBON-β′2mp at the lowest or medium-dose enhances CS+ reversal. n = 16,6,8; 22,12,10; 15,14,9 groups of flies. Statistical comparison as in (b). d Experimental protocol for assessing innate valence. Flies’ preference for red light illuminated versus unilluminated quadrants is quantified. (e) Flies expressing Chrimson in MBON-γ2α′1 avoid red light quadrants at low light intensity relative to genetic control, and prefer red-light quadrants at the highest light intensity. Flies expressing Chrimson in MBON-β′2mp are relatively attracted to red light quadrants at the lowest light intensity, and avoid red light quadrants at higher intensities. n = 11,6,10; 6,7,7; 7,7,7; 12,7,11; 5,5 groups of flies. Statistical comparison is by two-way ANOVA with Dunnett’s multiple comparisons test against empty-splitGAL4 control. f Proposed connectivity between potential upstream neurons and PAM-β′2a. For MBON-γ2α′1 or MBON-β′2mp to be the upstream neuron of PAM-β′2a, their activation would have to excite (+) or inhibit (−) PAM-β′2a, respectively. g Mean neural response in GCaMP6m-expressing PAM-β′2a when Chrimson-expressing MBON-γ2α′1 is activated (“+590 nm”, red) and mock activated (“−590 nm”, gray); red arrow indicates onset of red light. Bar graphs represent mean neural activity 1 s after red light onset. Activating MBON-γ2α′1 increases PAM-β′2a activity. n = 9 flies. Statistical comparison as in Fig. 3g. h Activating MBON-β′2mp and MBON-γ5β′2a does not significantly change PAM-β′2a activity. n = 7 flies. All error bars are mean ± SEM. Statistical comparison as in Fig. 3g, n.s. not significant, *p < 0.05, **p < 0.01, ***p < 0.001. i Proposed role of MBON-γ2α′1 and PAM-β′2a during aversive memory reversal. MBON-γ2α′1 CS+ odor response decreases and increases during memory acquisition and reversal, respectively, causing a corresponding decrease and increase in PAM-β′2a CS+ odor response via an excitatory connection (+).