CBS vs PSP Phenotype Determinants — Single-Nucleus Multi-Omics Study

SUMMARY

# CBS vs PSP Phenotype Determinants — Single-Nucleus Multi-Omics Study ## Background and Rationale Corticobasal syndrome (CBS) and progressive supranuclear palsy (PSP) represent distinct clinical phenotypes of 4-repeat tauopathy, yet the molecular determinants underlying their divergent presentations remain poorly understood. Both conditions share similar tau isoform pathology but exhibit markedly different anatomical distribution patterns, clinical presentations, and disease progression rates.

METHODOLOGY NOTES

Phase 1 (Months 1-3): Tissue procurement and processing. Obtain fresh-frozen post-mortem brain tissue from CBS (n=15), PSP (n=15), and age-matched controls (n=15) within 12-hour post-mortem interval. Dissect motor cortex, subthalamic nucleus, dentate nucleus, and frontal cortex regions using standardized anatomical landmarks. Flash-freeze samples in liquid nitrogen and store at -80°C. Phase 2 (Months 4-8): Single-nucleus isolation and library preparation. Generate single-nucleus suspensions using optimized sucrose gradient protocol with DAPI staining for nuclei verification. Prepare single-nucleus RNA-seq libraries using 10x Genomics Chromium platform targeting 10,000 nuclei per sample. Generate single-nucleus ATAC-seq libraries using 10x Multiome workflow with 5,000 nuclei per sample. Perform quality control including nuclei viability assessment and library complexity validation. Phase 3 (Months 6-10): Spatial transcriptomics and tau analysis. Process adjacent 10μm tissue sections for