Insights into the Biology of Hearing and Deafness Revealed by Single-Cell RNA Sequencing

Single-cell RNA sequencing is a powerful tool by which to characterize the transcriptional profile of low-abundance cell types, but its application to the inner ear has been hampered by the bony labyrinth, tissue sparsity, and difficulty dissociating the ultra-rare cells of the membranous cochlea. Herein, we present a method to isolate individual inner hair cells (IHCs), outer hair cells (OHCs), and Deiters’ cells (DCs) from the murine cochlea at any post-natal time point. We harvested more than 200 murine IHCs, OHCs, and DCs from post-natal days 15 (p15) to 228 (p228) and leveraged both short- and long-read single-cell RNA sequencing to profile transcript abundance and structure. Our results provide insights into the expression profiles of these cells and document an unappreciated complexity in isoform variety in deafness-associated genes. This refined view of transcription in the organ of Corti improves our understanding of the biology of hearing and deafness. [Display omitted] •Single-cell RNA-seq identifies inner and outer hair cell defining genes by AUC-ROC•Sorcin, a key component for cardiac excitation-contraction, is a top marker of OHCs•Analysis of deafness-associated genes identifies heretofore unrecognized exons•Nanopore long-read RNA-seq reveals splicing diversity and isoform abundance Single-cell RNA-seq of inner and outer auditory hair cells facilitates the identification of cell type-defining genes across a range of expression levels. Full-length reverse transcription with long-read sequencing identifies novel exons and unappreciated splicing diversity among deafness-associated genes.