Building a somatosensory atlas for interoception - Project Summary/Abstract Somatosensory neurons are well-known for innervating skin and muscle and transmitting sensations such as touch, pain, itch, and proprioception to the brain. However, these same type of heterogeneous set of neurons also innervate internal organs and are responsible to convey information of the internal state of our body. These interoceptive signals include both conscious (bladder fullness) and subconscious (blood pressure) senses. Despite their importance, we do not know their projection patterns and physiological roles. Here, we propose to use a set of innovative tools that will allow us to specifically label, visualize, and isolate sensory neurons innervating various internal organs. Using a variety of state-of-art molecular, imaging, and genomic techniques, we will build an anatomical database of these neurons and use snRNAseq to establish the molecular identities of individual sensory neurons based on their innervating organs. Finally, the anatomical, cellular, and molecular maps will be standardized, indexed, and integrated into an atlas that will allow the community to freely access the data.