Hnrnpa21 regulates myogenic fate plasticity
RNA-binding proteins (RBPs) are essential for skeletal muscle regeneration and RBP dysfunction causes muscle degeneration and neuromuscular disease (NMD). How the timing of RBP function governs the complex cell fate decisions during muscle regeneration is poorly understood. Here, single cell analysis of skeletal muscle regeneration reveals the timing of NMD-associated RBPs expression in muscle progenitors, including a massive upregulation of Hnrnpa2b1 (A2b1). A2b1 promotes muscle progenitor plasticity by regulating the splicing of RNAs expressed at specific times during the trajectory of muscle differentiation. Using RBP-RNA engagement scoring and machine learning, we accurately predict NMD-associated RBP functionality in directing myogenesis. Together our analysis reveals how A2b1 regulates myogenic plasticity and provides a broadly applicable single cell methodology for examining how RBPs influence complex cell fate trajectories. Overall design: RNA-seq in differentiating hnrnpa2b1 KO and WT c2c12 cells