The Role of Alternative Splicing in FSHD Disease Models - Facioscapulohumeral muscular dystrophy (FSHD) is a prevalent form of muscular dystrophy caused by the aberrant expression of the transcription factor DUX4, which leads to muscle toxicity and progressive weakness. While previous research has identified transcriptional changes induced by DUX4, the mechanisms through which DUX4 affects RNA processing, particularly alternative splicing, remain largely unexplored. Alternative splicing is critical for muscle function, and its disruption may exacerbate muscle pathology in FSHD. This project aims to investigate the role of DUX4 in regulating alternative splicing, with the goal of developing an RNA splicing biomarker for FSHD. The proposed research includes three specific aims. First, the project will characterize the interactions between DUX4 and RNA in muscle cells to identify RNA targets of DUX4 that undergo alternative splicing (Aim 1). Second, the role of DUX4 in regulating the alternative splicing of TNNT1—a gene essential for muscle contraction that is abnormally spliced in FSHD—will be explored, focusing on the potential cooperation between DUX4 and splicing factors hnRNP U, DDX5, and FUS (Aim 2). Third, the project will develop an RNA splicing biomarker for FSHD by identifying and validating splicing changes in patient-derived myotubes and iPSC-derived myotubes (Aim 3). To achieve these aims, the project will utilize advanced methodologies, including RNA-seq, CLIP-seq, and splicing analysis tools such as DEXSeq. The research is expected to uncover molecular mechanisms through which DUX4 disrupts splicing in FSHD, which may provide a foundation for future diagnostic and therapeutic strategies. These findings will be crucial for developing clinical trials that assess splicing biomarkers in FSHD patients. This award will provide the applicant with the training and expertise in bioinformatics and RNA biology necessary to become an independent investigator. Under the mentorship of experts in the field, the applicant will gain proficiency in analyzing next-generation sequencing data and conducting complex RNA biology assays. This project will establish a strong foundation for a research program focused on gene regulation in muscular dystrophies and contribute to the development of targeted therapies for FSHD.
