Total RNA from 10 mg brain tissue samples was extracted using the RNeasy Mini Kit according to manufacturer's protocol (Qiagen 74004) and resuspended in 30 μl nuclease-free water.Total RNA from 10 mg brain tissue samples was extracted using the RNeasy Mini Kit according to manufacturer's protocol (Qiagen 74004) and resuspended in 30 μl nuclease-free water. Library preparation contains the following steps: 1. Poly-A mRNA capture and reverse transcription for cDNA synthesis: oligo-dT primer to capture just the mRNA (contains sample barcode, UMI, and Read 1 sequences). 2. Second strand synthesis and tagmentation: double stranded-cDNA is generated. Tagmentation creates fragments and incorporates Read 2 sequence. 3. Illumina library amplification: adds unique dual indices (UDI = i5, i7) and P5/P7 sequences.