Description
Integration of nutritional, microbial and inflammatory events along the gut-brain axis can alter bowel physiology and organism behaviour. The principal neural unit in the bowel encoding these stimuli is the visceral sensory neuron with endings at the mucosa, intramurally and along mesenteric blood vessels. Sensory neurons activate reflex pathways and give rise to conscious sensation, however, the diversity and division of function within these neurons is poorly understood. The identification of signalling pathways contributing to visceral sensation is constrained by the current paucity of molecular markers. Here we overcome these limitations by comprehensive transcriptomic profiling and unsupervised clustering of single colonic sensory neurons revealing 7 classes characterised from both lumbar splanchnic (LSN) and pelvic nerves (PN). We identify and classify neurons based on novel marker genes, confirm translation of patterning to protein expression and show subtype-selective differential agonist activation, describing sensory diversity encompassing all modalities of colonic neuronal sensitivity. Overall design: Sensory neurons innervating the mouse colorectum were labelled by retrograde tracer injection. Single-cell RNAseq was performed on 399 dissociated colonic sensory neurons isolated from thoracolumbar (T10-L1) and lumbosacral (L5-S2) dorsal root ganglia distributed over six 96-well plates. 13 additional negative controls were collected.