DPA and MTN neurons were labeled with 1,1'-Dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI) from the maxillary first molars of C57BL/6  mouse, then isolated in acute culture from the TG tissues and from brainstem slices, respectively. Afterwards, they were manually collected using a glass micropipette containing RNase inhibitor; each neuron was also photographed prior to collection, and the images were used for cell body area (μm2) measurements using ImageJ software. Neurons were individually digested and reverse-transcribed into non-stranded cDNA using poly-T primers. The resulting cDNA was amplified using SMART-Seq v4 Ultra Low Input RNA kit according to the manufacturer's instructions, but with the following modifications: 1) ERCC RNA Spike-In controls were added at the cell lysis step 2) 18 PCR cycles were performed to amplify cDNA libraries. The libraries were diluted accordingly and used to make DNA sequencing libraries by following the Nextera XT DNA Library Preparation Kit protocol. Library size distribution and quality were measured using Agilent's BioAnalyzer High Sensitivity DNA assay prior to sequencing.