Fig. 4

ORs differentially expressed between SF and SM mice detect sex-specific odors. a FISH analyses of Egr1 expression within the MOE following exposure of a male mouse to a group of female mice (♂ exposed to ♀; left) or a female mouse to a group of male mice (♀ exposed to ♂; right). b–d Representative images of two-color RNA-FISH analyses of Olfr912 and Egr1 co-expression following exposure of a female mouse to a group of male mice (b), a female mouse to clean bedding (c), or a male mouse exposed to a group of female mice (d). Arrows: locations of representative Olfr912-expressing cells. e, f Quantification, based on two-color RNA-FISH, of the fraction of Olfr912-expressing (e) and Olfr235-expressing (f) OSNs that co-express Egr1 within the MOE of a male mouse exposed to 4 female mice for 40 min (M→F), a female mouse exposed to 4 male mice for 40 min (F→M), a male mouse exposed to clean bedding (M(–)), or a female mouse exposed to clean bedding (F(–)).*p < 0.05, **p < 0.01 (two-tailed t test); n = 3 MOE sections (average of 52 Olfr912-expressing and 56 Olfr235-expressing OSNs/section). Error bars: s.e.m. Dots represent average values for individual sections. g Quantification, based on two-color RNA-FISH, of the fraction of the indicated OR-expressing OSNs that co-express Egr1 within the MOE of individual male mice exposed to 4 females (♀ mice) or female mice exposed to 4 males (♂ mice) for 40 min SF-biased (SF > SM) and SM-biased (SM > SF) ORs (based on RNA-seq) are highlighted in pink and blue, respectively. ORs shown to have differential expression frequencies in SF and SM mice are grouped separately (top). Olfr867 is a representative negative control OR. Statistical analysis results in g are based on comparisons between the fractions of OSNs co-expressing Egr1 after exposure to either female or male mice. *p < 0.05, **p < 0.01 (two-tailed t test); n = 3 MOE sections (average of 60 specific OR-expressing OSNs/section). Scale bars for a: 500 µm; b–d: 100 µm