Striated muscles represent a significant fraction of the organism’s body weight in vertebrates. While historically skeletal muscles were generally considered to have similar properties throughout the body, over the last decades it became clear that the developmental origins and regenerative capacities of muscle stem and differentiated cells show surprising diversity. Our laboratory hypothesized that the different developmental origins of cranial and trunk muscle groups may have a long-term impact on the functional properties of their myofibers and their resident muscle stem cells (MuSCs).
To establish the profile of each muscle, we will use single nucleus RNA and ATAC-seq data on limb (Tibialis anterior, TA) and craniofacial (Extraocular (EOM), Esophagus (ESM)) muscles.
Interestingly, EOMs possess numerous specific features, including multiple innervation (Kupfer, 1960), increased density of MuSCs (Keefe et al., 2015), non-canonical types of tendon attachments (Comai et al., 2020), expression of unique myosins heavy chains (Myh13, Myh14, Myh15) and of developmental myosins (Myh3, Myh8) throughout life (Hoh, 2021). EOMs are also spared in dystrophic disease and aging. In this project we aim at uncovering the molecular and cellular basis of these unique features.
