Fig. 2: The knockout of Ms4a6c impairs the ability of necklace OSNs to detect DMP, a predator-derived compound, but does not significantly affect DMP-mediated innate avoidance behavior.

A Example images of the cul-de-sac regions of the main olfactory epithelia of mice exposed to the indicated odorant, co-labeled for the necklace cell marker, Car2 (magenta), and the neuronal activity marker, phospho-S6 (pSerine240/244) (green), from wildtype (left panels) or Ms4a6c knockout animals (right panels). B Quantification of the average pS6 signal/necklace cell above the average pS6 signal/necklace cell when no odor is introduced (water) in wildtype mice (left panel) or Ms4a6c knockout mice (right panel) when exposed to the indicated odors. Data are presented as mean ± SEM. For wildtype mice (left panel), n = 360 cells over five independent experiments (EUG), n = 404 cells over six independent experiments (CS₂), n = 459 cells over six independent experiments (2,5-DMP), n = 611 cells over four independent experiments (2,3-DMP), n = 467 cells over four independent experiments (OA); for Ms4a6c knockout mice (right panel), 269 cells over three independent experiments (EUG), n = 351 cells over four independent experiments (CS₂), n = 193 cells over five independent experiments (2,5-DMP), n = 281 cells over three independent experiments (2,3-DMP), n = 501 cells over four independent experiments (OA). The number of independent experiments (mice) is indicated in brackets, **p < 0.01, ****p < 0.0001, Dunnett’s test following one-way ANOVA compared to eugenol exposure. C Heat maps of the occupancy of wildtype (left panels) or Ms4a6c knockout mice (right panels) in the odor avoidance chamber in response to the indicated odorants. Small square represents the location of the odorant, and the dashed line demarcates the odor avoidance zone from the rest of the chamber. Scale bar, 5 cm. D Quantification of odor avoidance behavior. The distance between the average center of mass of the mouse and the location of the odorant (top panels) and the proportion of time spent in the odorized zone (bottom panels) were determined for wildtype mice (left) and Ms4a6c knockout mice (right). Each circle represents an individual mouse. Data are presented as mean ± SEM. For wildtype mice (left panels), n = 20 mice over 13 independent experiments (Blank), n = 5 mice over five independent experiments (Water), n = 8 over four independent experiments (2,5-DMP), n = 5 mice over four independent mice (TMT); for Ms4a6c knockout mice (right panels), n = 16 mice over nine independent experiments (Blank), n = 8 mice over four independent experiments (Water), n = 10 mice over five independent experiments (2,5-DMP), n = 5 mice over four independent experiments (TMT). *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001, Dunnett’s test following one-way ANOVA compared to water exposure. Source data are provided as a Source Data file.