GSE64091
Transcriptional profiling of cutaneous Mrgprd free nerve endings and C-LTMRs
Cutaneous C-unmyelinated free nerve endings and hair follicles-innervating C-LTMRs convey two opposite aspects of touch sensation: a sensation of pain and a sensation of pleasant touch. The molecular mechanisms underlying these diametrically opposite functions are unknown. Here we used a mouse model that genetically marks C-LTMRs and the free nerve endings MRGPRD+ neurons in combination with fluorescent cell surface labeling, flow cytometry and RNA deep-sequencing technology. Cluster analysis of the RNA-Seq profiles of the purified neuronal subsets revealed 156 and 184 genes differentially expressed in MRGPRD-expressing neurons and C-LTMRs, respectively. 48 MRGPD- and 67 C-LTMRs-enriched genes were validated using a triple staining experiment approach and the Cav3.3 channel, found to be exclusively expressed in C-LTMRs, was validated using electrophysiology. Furthermore, our study greatly expands the molecular characterization of C-LTMRs and suggests that this particular population of neurons shares common transcriptional signatures with A and A low threshold mechanoreceptors. Overall design: RNA profiles of FACS-sorted subsets of sensory neurons, namely Mrgprd+ neurons (DP, double-positive=IB4+GINIP+), C-LTMRs (IB4-GINIP+) and remaining cells (DN, double-negative=IB4-GINIP-) were generated by deep sequencing in duplicate using Illumina HiSeq 2000.