total mRNA of DRG was isolated using the Qiagen AllPrep kit (cat. no. 80004) for simultaneous mRNA/DNA/protein. RNA integrity was assessed via Bioanalyzer 2100 (Agilent Technologies, CA, USA). Messenger RNA is purified from total RNA using poly-T magnetic beads, fragmented, and converted to cDNA using random hexamer primers, with second-strand synthesis using dTTP for non-strand-specific libraries or dUTP for strand-specific libraries. Both library types undergo end repair, A-tailing, adapter ligation, size selection, amplification, and purification, followed by quality control using Qubit, real-time PCR, and a bioanalyzer. Libraries are then pooled and sequenced on an Illumina platform to analyze gene expression.