Muscle development and regeneration in normal and pathological conditions: learning from Drosophila.

The recent demonstration that, throughout evolution, many molecular mechanisms have been highly conserved is fundamental to the advancement of our knowledge on muscle development and regeneration. Research has provided new insights into genetic cascades governing early steps of embryonic myogenesis and the regeneration of adult muscle in normal and pathological conditions, thus revealing significant similarity of both processes. Here we provide a current view on genetic mechanisms underlying muscle regeneration with a special focus on regeneration processes that take place in diseased and aging human muscle. Through examples of Drosophila models of human muscular diseases, we discuss potential impact they might have on uncovering molecular bases and identifying new treatments of muscle disorders. Taking advantage of evolutionarily conserved aspects of muscle development and the relative ease by which molecular pathways can be uncovered and dissected in a simple animal model, the fruit fly, we provide a comprehensive analysis of muscle development in Drosophila. Importantly, identification of muscle stem cell like adult muscle precursors in Drosophila makes fruit fly an attractive model system for studying muscle stem cell biology and muscle regeneration. In support of this assumption, recent studies in our laboratory provide arguments that important insights into the biology of vertebrate muscle stem cells can be gained from genetic analysis in Drosophila.