Huang, PengRuel, Tyler David2019-12-202019-12-202019-12-20Ruel, T. D. (2019). Characterization of Muscle-Associated Cells in Adult Zebrafish (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.http://hdl.handle.net/1880/111373Skeletal muscles make up 40% of body weight in humans. Any compromises in muscle function will cause major consequences to the quality of a person’s life. It is therefore extremely important that this tissue is maintained in a state of homeostasis. To do this, muscle fibres that become damaged must be repaired by tissue-resident muscle-stem cells throughout the life of an animal. Several different kinds of muscle-associated cells have been described, including the two main populations: satellite cells (a population of muscle stem cells) and fibro/adipogenic progenitors (FAPs) (a population of mesenchymal stem cells). Using zebrafish as a model, the importance of muscle-associated cells in maintaining muscle homeostasis is demonstrated. Our lab has previously generated a col1a2¬-based transgenic line that labels collagen-expressing cells in zebrafish. Using a combination of immunohistochemistry and confocal microscopy, I characterize the dynamics and function of col1a2+ muscle-associated cells. A developmental time course shows that col1a2+ intramuscular cells increase in numbers during juvenile stages. In response to muscle injury, col1a2+ muscle-associated cells are expanded and contribute to muscle regeneration. Genetic ablation of col1a2+ cells, results in a compromised regenerative response. Using Cre-mediated lineage tracing, the developmental origin of intramuscular cells is traced to the dermomyotome and sclerotome, two sub-compartments of the embryonic somite. Finally, characterization of a col1a2 mutant line of zebrafish suggests that Type-I collagen is important for maintaining muscle integrity. These observations suggest the importance of col1a2+ muscle-associated cells in maintaining muscle homeostasis and for producing the extracellular matrix (ECM) within the skeletal muscle tissue to prevent degeneration.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.MuscleSatellite CellFibroadipogenic ProgenitorZebrafishcol1a2Extracellular MatrixRegenerationBiology--MolecularBiochemistrymaster thesis10.11575/PRISM/37365