Abstract:
<p>The chemical cues that provide an olfactory portrait of mammalian individuals are in part detected by chemosensory receptors in the vomeronasal organ (VNO). By and large, the pertinent receptor-cue combinations used for olfactory communication are unidentified. Here we identify members of the formyl peptide receptor (FPR) family of G protein coupled receptors as candidate chemosensory receptors in the VNO of mice. We demonstrate that N-formylated mitochondrially encoded peptides presented by the major histocompatibility complex (MHC) molecule H2-M3 stimulate a subset of the VNO sensory neurons (VSNs). We show that one VNO localized FPR, Fpr-rs1, is differentially activated by strain specific variants of N-formylated peptides. We show that N-formylated peptides can function as chemosignals in a strain selective pregnancy block. We propose that this link between self-recognition peptides of the immune system and chemosensory pathways provides a possible molecular means to communicate the nature of an individual's maternal lineage or strain.</p>
