A sexually dimorphic neuroendocrine cascade acts through shared sensory neurons to regulate behavior in C. elegans

ABSTRACT\n\nSexually dimorphic behaviors are observed in species across the animal kingdom, however the relative contributions of sex-specific and sex-shared nervous systems to such behaviors are not fully understood. Building on our previous work which described the sexually dimorphic expression of a neuroendocrine ligand, DAF-7, and its role in behavioral decision-making in C. elegans (Hilbert and Kim, 2017), we show here that sex-specific expression of daf-7 is regulated by another neuroendocrine ligand, Pigment Dispersing Factor (PDF-1), which has previously been implicated in regulating male-specific behavior (Barrios et al., 2012). Our analysis revealed that PDF-1 acts sex- and cell-specifically in the ASJ neurons to regulate the expression of daf-7 and we show that differences in the expression of the PDFR-1 receptor account for the sex-specific effects of this pathway. Our data suggest that modulation of the sex-shared nervous system by neuroendocrine signaling pathways can play a role in shaping sexually dimorphic behaviors.