Single-cell mRNA isoform diversity in the mouse brain. Mus musculus

Single-cell isoform regulation is increasingly being studied. To get a full view of alternative isoform usage, from transcription start site and alternative splicing to transcription termination site, full-length sequences have to be studied. Here we use PacBio long read sequencing technology combined with unique molecular identities to get a full and accurate picture of alternative isoform usage of different stages in maturing oligodendrocyte single cells. We see that the majority of molecules in single-cells are separate isoforms, even after applying a conservative definition of what constitutes an isoform. Few isoforms are common between cells of the same cell-type but the common isoforms are higher expressed. We also see that exon junctions in coding regions are better regulated than exon junctions in non-coding regions and that genes often express more than one coding isoform. Overall design: Six samples analysed, no replicated

单细胞异构体调控正日益受到学界关注。为全面解析可变异构体的使用模式——从转录起始位点（transcription start site）、可变剪接（alternative splicing）直至转录终止位点（transcription termination site），必须对全长序列展开研究。本研究结合PacBio长读长测序技术（PacBio long read sequencing technology）与唯一分子标识符（unique molecular identities），旨在全面且精准地刻画成熟进程中不同阶段的少突胶质细胞（oligodendrocyte）单细胞的可变异构体使用图谱。研究发现，即便采用保守的异构体定义标准，单细胞内的绝大多数分子均为单一异构体。同一细胞类型的细胞间共享的异构体寥寥无几，但共享异构体的表达水平显著更高。此外，本研究还观察到，编码区的外显子连接位点（exon junctions）相较于非编码区（non-coding regions）的外显子连接位点受到更严谨的调控，且单个基因通常可表达多种编码异构体。实验整体设计：共分析6个样本，未设置生物学重复。