Fig 2: OXT signaling in aromatase-expressing neurons is required for the discrimination of male and female conspecifics.(A) Male mice lacking AVP signaling showed normal preference for female conspecific cues. Left: time spent investigating each odor cue. Upper right: odor preference score; Bottom right: total time spent in the investigation of odor cues. t test, ***p<0.001, ns, not significant. (B) Male mice lacking OXT signaling in Cyp19a1 (aromatase)-expressing neurons (A-Oxtrflox/flox) have impaired preference for female conspecifics in the 3-chamber social preference test. Upper: time spent in each interaction zone. Bottom: social preference score. t test, ***p<0.001, **p<0.01, ns, not significant. (C) Comparison of control (Oxtrflox/flox) and Trh-Cre; Oxtrflox/flox (T-Oxtrflox/flox) mice in social interaction preference using the 3-Chamber paradigm. Upper: time spent in each interaction zone. Bottom: social preference score. t test, ***p<0.001, **p<0.01, *p<0.05. (D) Y-maze paradigm testing the willingness of control and A-Oxtrflox/flox male mice to investigate food vs. fox urine spiked food. t test, **p<0.01, *p<0.05. (E) Responses of control and T-Oxtrflox/flox mice to predator cues and female cues in a Y-maze paradigm. t test, *p<0.05. (F) Male mice lacking OXTR (A-Oxtrflox/flox) in aromatase-expressing neurons have impaired preference for female olfactory cues. Upper: time spent investigating each odor cue. Middle: odor preference score. Bottom: total time spent in the investigation of odor cues. t test, **p<0.01, ***p<0.001, ns, not significant.

Fig 3: Expression of Cry1::EGFP in mouse brain by in vivo application of translational switching. (A and B) Representative low-power (20×) photomicrographs of a coronal SCN section from a Cry1,2-null mouse injected with AAV pCry1-EGFP (A) or pCry1-Cry1::EGFP (B). (Scale bar: 100 µm.) (C) Representative photomicrographs of a coronal SCN section from a Cry1,2-null mouse showing colocalization of the mCherry reporter of PylRS and the translationally controlled pCry1-Cry1(177TAG)::EGFP protein in the SCN at 20× magnification (Upper Row) and 63× magnification (Bottom Row). (Scale bars: 100 µm, Upper Row; 10 µm, Bottom Row.) (D) Representative 4 × 4 tiled photomicrographs of coronal sections showing the rostro-caudal extent of the AAV-mediated expression of pCry1-Cry1(177TAG)::EGFP in the hypothalamus. (Magnification: 20×.) 3V, third ventricle; AC, anterior commissure; MBH, medio-basal hypothalamus; OC, optic chiasm; POA, preoptic area. (Scale bar: 500 µm.) (E) Representative photomicrographs show the colocalization of AAV pCry1-Cry1(177TAG)::EGFP with the mCherry reporter of PylRS and either AVP (Upper Row) or VIP (Lower Row) immunoreactivity. (Magnification: 63×.) (Scale bars: 20 µm.) (F) Representative photomicrographs show the colocalizations of pCry1-Cry1(177TAG)::EGFP with the bio-orthogonal click label AzAF647, confirming the incorporation of AlkK into translationally switched pCry1-Cry1(177TAG)::EGFP. (Magnification: 63×.) (Scale bar: 20 µm.)

Fig 4: Schematic representations of the connections between peptidergic neuronal types. The numbers and the arrow thickness indicate the proportion of cells receiving more than or equal to three appositions (statistics in Tables 2, 3). A, In WT mice, there was a preferential unilateral direction of communication between AVP-VIP and GRP-CALR (blue). While the other connections indicated are all reciprocal, there are few AVP to VIP contacts and more GRP to CALR contacts than the converse (***p < 0.001, **p = 0.008). B, In contrast to WT mice, in VIP-KO mice, there was no evidence of preferential direction of communication between peptidergic cell types.

Fig 5: Relationship between anxiety and nest buildinga) Fraction of time in the open arms of an elevated plus maze. Line at the mean. ****, P<0.0001 for difference between species by two-way ANOVA with sex and species as factors. No significant effect of sex or sex-by-species interaction. b) Spearman correlation coefficients among F2s between fraction of time in the open arms and parental behaviours. Handling and approach are promptness to perform those behaviours. c) Linkage (lod score) to chromosome 4 of nest building behaviour and fraction of time in open arms. Males and females combined since there are no major differences in the lod scores between sexes. Red line denotes the location of Avp. Dashed lines denote the P=0.05 genome-wide significance level determined by 1,000 permutations of each trait (n=769).