Project description:We performed RNA sequencing of genetically labeled MrgprA3+ neurons under both naïve and allergic contact dermatitis conditions. Our results revealed the unique molecular signature of itch-sensing neurons and the distinct transcriptional profile changes that result in response to dermatitis. We found enrichment of nine Mrgpr family members and two histamine receptors in MrgprA3+ neurons, suggesting that MrgprA3+ neurons are a direct neuronal target for histamine and Mrgprs agonists. In addition, Ptpn6 and Pcdh12 were identified as novel and highly selective markers of MrgprA3+ neurons. We also discovered that MrgprA3+ neurons respond to skin dermatitis in a way that is unique from other sensory neurons by regulating a combination of transcriptional factors, ion channels, and key molecules involved in synaptic transmission. These results significantly increase our knowledge of itch transmission and uncover potentially novel targets for combating itch.
Project description:To identify the molecular signature of leucine-activated neurons in the MBH, we adopted the PhosphoTRAP assay following parenchymal injection of leucine into the MBH. Neurons activated following MBH leucine injection (and expressing the neuronal activation marker cFos) co-express Ser240/244-phosphorylated ribosomal S6 protein , allowing selective immunoprecipitation-based capture (TRAP) and RNA sequencing of polysomes from leucine-activated neurons. Differential expression analysis between IP and input samples generated a list of enriched transcripts in leucine-activated neurons