Metazoan muscle re-generation: what can we learn from diversity?

With the exception of neurosciences and in particular the evolution of neuronal networks, comparisons of molecular mechanisms underlying given biological processes between invertebrates and vertebrates have received only limited attention. Similar to the nervous system, cells with contractile functions (i.e. muscles) are, with the exception of placozoan, present throughout the metazoan tree of life. Moreover, maintenance of tissue homeostasis through muscle regeneration is a common fundamental process found from morphologically simple (i.e. cnidarians) to more complex (i.e.. vertebrates) animals. Thus, the variety of muscle morphology, its bio-mechanic, genetic, developmental and regeneration strategies makes muscle tissue a precious model to investigate the existing relationships of metazoan muscles. Although mammalians display restricted capacities to re-form missing tissues or structures, a wide variety of metazoans display extraordinary regenerative capacity. In particular, members of the Cnidaria, Annelida, Mollusca, Nemertenea, Platyhelminta, Echinodermata and certain Chordata including vertebrates such as the Axolotl (Ambystoma mexicanum) are well known for their high regenerative capacities. However, even if the ability to regenerate is widespread in the animal kingdom, the strategies, cell type involvement and extent of regeneration may profoundly vary across diverse phyla. Here we want to address the importance of this diversity. Given its unique evolutionary history, each animal can answer specific questions and contribute to the final puzzle of muscle re-generation programming/reprogramming pathways.


The aim of the proposed Research Topic in Frontiers in Cell and Developmental Biology is to provide an overview of i) the main animal muscle types existing in the animal kingdom, ii) highlight the importance to study muscle programming/reprogramming in a given phylum/species and iii) the current knowledge about the molecular mechanisms underlying muscle formation and/or regeneration. While we do not aim at providing a detailed and complete overview of the potentiality of each of the examined species we want to draw the attention at the unique aspect of their muscles and on the specific questions that can be addressed by studying them. By doing so, we believe that this Research topic will identify not only conserved but also ‘divergent’ strategies developed during the evolution of the tissue homeostasis and regeneration. This may provide new concepts on the cellular and molecular mechanisms of muscle regeneration and foster future comparative investigations on muscle reprogramming.