Long noncoding RNAs at the interface between muscles and nerves”

Extensive high-throughput analyses and innovative biochemical approaches have unveiled, beyond protein factors, the additional and essential contribution of RNA-mediated molecular mechanisms in the regulation of myogenic gene expression. In particular, tissue-specific long noncoding RNAs (lncRNAs) were shown to play pivotal roles in muscle physiology and development, although the knowledge concerning their mechanisms of action is still far from being complete. Our aim is to study the contribution of lncRNAs to muscular and neuromuscular physiology through the integration of gene editing, induced pluripotent stem (iPS) cell technology and interactome analyses. Our investigations include Charme (Taliani V. et al., Elife 2023), previously identified in mice as a myogenic lncRNA, and currently under investigation in human skeletal muscle differentiation. Emphasis is also placed on the impact of lncRNA on muscle-nerve communication, specifically focusing on the spinal cord and skeletal muscle functional interactions at the neuromuscular junction (NMJ). By applying CRISPR-cas9 genome editing we generated human iPSCs lines knocked out for either Charme or the motoneuronal lncRNA nHotairM1 (Tollis P. et al., Cell Death & Dis 2023). We exploit co-cultures of iPSC-derived spinal motoneurons and myotubes and 3D model systems (neuromuscular organoids) to untangle the contributions of neural and muscular lncRNAs to the structural and functional properties of the NMJ.