RT Journal Article SR Electronic T1 Single-cell RNA counting at allele- and isoform-resolution using Smart-seq3 JF bioRxiv FD Cold Spring Harbor Laboratory SP 817924 DO 10.1101/817924 A1 Michael Hagemann-Jensen A1 Christoph Ziegenhain A1 Ping Chen A1 Daniel Ramsköld A1 Gert-Jan Hendriks A1 Anton J.M. Larsson A1 Omid R. Faridani A1 Rickard Sandberg YR 2019 UL http://biorxiv.org/content/early/2019/10/25/817924.abstract AB Large-scale sequencing of RNAs from individual cells can reveal patterns of gene, isoform and allelic expression across cell types and states1. However, current single-cell RNA-sequencing (scRNA-seq) methods have limited ability to count RNAs at allele- and isoform resolution, and long-read sequencing techniques lack the depth required for large-scale applications across cells2,3. Here, we introduce Smart-seq3 that combines full-length transcriptome coverage with a 5’ unique molecular identifier (UMI) RNA counting strategy that enabled in silico reconstruction of thousands of RNA molecules per cell. Importantly, a large portion of counted and reconstructed RNA molecules could be directly assigned to specific isoforms and allelic origin, and we identified significant transcript isoform regulation in mouse strains and human cell types. Moreover, Smart-seq3 showed a dramatic increase in sensitivity and typically detected thousands more genes per cell than Smart-seq2. Altogether, we developed a short-read sequencing strategy for single-cell RNA counting at isoform and allele-resolution applicable to large-scale characterization of cell types and states across tissues and organisms.