Single-nucleus transcriptomic analysis reveals the regulatory circuitry of myofiber XBP1 during regenerative myogenesis
Aniket S. Joshi,
Micah B. Castillo,
Meiricris Tomaz da Silva,
Anh Tuan Vuong,
Preethi H. Gunaratne,
Radbod Darabi,
Yu Liu,
Ashok Kumar
Affiliations
Aniket S. Joshi
Institute of Muscle Biology and Cachexia, University of Houston College of Pharmacy, Houston, TX 77204, USA; Department of Pharmacological and Pharmaceutical Sciences, University of Houston College of Pharmacy, Houston, TX 77204, USA
Micah B. Castillo
Department of Biology and Biochemistry, University of Houston, Houston, TX 77204, USA
Meiricris Tomaz da Silva
Institute of Muscle Biology and Cachexia, University of Houston College of Pharmacy, Houston, TX 77204, USA; Department of Pharmacological and Pharmaceutical Sciences, University of Houston College of Pharmacy, Houston, TX 77204, USA
Anh Tuan Vuong
Institute of Muscle Biology and Cachexia, University of Houston College of Pharmacy, Houston, TX 77204, USA; Department of Pharmacological and Pharmaceutical Sciences, University of Houston College of Pharmacy, Houston, TX 77204, USA
Preethi H. Gunaratne
Department of Biology and Biochemistry, University of Houston, Houston, TX 77204, USA
Radbod Darabi
Institute of Muscle Biology and Cachexia, University of Houston College of Pharmacy, Houston, TX 77204, USA; Department of Pharmacological and Pharmaceutical Sciences, University of Houston College of Pharmacy, Houston, TX 77204, USA
Yu Liu
Institute of Muscle Biology and Cachexia, University of Houston College of Pharmacy, Houston, TX 77204, USA; Department of Biology and Biochemistry, University of Houston, Houston, TX 77204, USA
Ashok Kumar
Institute of Muscle Biology and Cachexia, University of Houston College of Pharmacy, Houston, TX 77204, USA; Department of Pharmacological and Pharmaceutical Sciences, University of Houston College of Pharmacy, Houston, TX 77204, USA; Corresponding author
Summary: Endoplasmic reticulum (ER) stress-induced unfolded protein response (UPR) is activated in skeletal muscle under multiple conditions. However, the role of the UPR in the regulation of muscle regeneration remains less understood. We demonstrate that gene expression of various markers of the UPR is induced in both myogenic and non-myogenic cells in regenerating muscle. Genetic ablation of X-box binding protein 1 (XBP1), a downstream target of the Inositol requiring enzyme 1α (IRE1α) arm of the UPR, in myofibers attenuates muscle regeneration in adult mice. Single nucleus RNA sequencing (snRNA-seq) analysis showed that deletion of XBP1 in myofibers perturbs proteolytic systems and mitochondrial function in myogenic cells. Trajectory analysis of snRNA-seq dataset showed that XBP1 regulates the abundance of satellite cells and the formation of new myofibers in regenerating muscle. In addition, ablation of XBP1 disrupts the composition of non-myogenic cells in injured muscle microenvironment. Collectively, our study suggests that myofiber XBP1 regulates muscle regeneration through both cell-autonomous and -non-autonomous mechanisms.
