Brain-Wide Characterization of Agouti Signaling Protein (ASIP) in the African Striped Mouse

Abstract

Parental behaviors play a pivotal role in the development and survival of offspring. While maternal care is well documented, paternal care remains less understood. African striped mice (ASM) offer a unique opportunity to investigate paternal care due to their biparental nature and adaptability to experimental techniques, stemming from their phylogenetic relatedness to Mus. Recent work in our lab demonstrated that Agouti (translated Agouti signaling protein, or ASIP) is expressed within the medial preoptic area (MPOA) of the ASM brain and integrates environmental cues to regulate paternal behavior. However, the spatial distribution of Agouti/ASIP beyond the MPOA remains unclear. Here, I investigated ASIP expression and its relation to melanocortin 4 receptor (c), a putative receptor of ASIP in the brain. I combined multiple approaches, including qPCR of microdissected brain regions, biotin–streptavidin amplified immunofluorescence, and RNAscope to assess Agouti mRNA, ASIP protein, and Mc4r mRNA. Agouti expression was detected beyond the MPOA, with enrichment in hypothalamic regions, the nucleus accumbens, and the lateral septum. Elevated Agouti expression within the MPOA did not correspond to brain-wide increases in expression. Subregional analyses revealed ASIP-positive cell populations and overlapping Agouti and Mc4r expression in multiple behaviorally relevant regions. Together, these findings demonstrate that ASIP is broadly distributed across the brain, but with region-specific localization, supporting a potential role as a neuromodulator within melanocortin circuits. This research provides insight into behavioral biology and contributes to a broader understanding of the neural mechanisms underlying parental care across species.