Omics profiling in echinoderms tissue and organ regeneration

The molecular pathways that trigger and are responsible for the amazing intrinsic regenerative ability that leads to a functional re-growth of echinoderms body-parts are still unknown. In order to approach this subject, several proteomic strategies were used to evaluate the impact of wound healing and tissue regrowth on starfish radial nerve cords, coelomocytes and coelomic fluid upon arm tip amputation. Additionally, a preliminary metabolomic study by ESI-MS/MS has been conduct on this fluid. Proteome and PTMomics changes across the different regeneration stages were analyzed in several protein fractions of the radial nerve cord and of the coelomic fluid using the 2D DIGE approach and specific stains for phospho and glycoproteins. The studied tissues have been pointed out as those more prone of involvement in star-fish regeneration, either as stem cell producers, enrolment in cell signaling and immunity response, among others. Our results show significant changes on proteome, phosphoproteome, glycome and metabolome profiles during wound healing and regrowth. Several functional classes of proteins known to be involved in regeneration events in other model organisms, such as chordates, were identified for the first time in echinoderm nervous system regeneration events and interestingly, some were found to be regulated at the post-translational level through proteolytic, phosphorylation or glycosylation pathways. Also, several proteins with no previous association with regeneration events were identified and are considered as interesting molecules for future studies further highlighting the importance of the contribution that echinoderms can add to the knowledge on tissue and organ regeneration. At the metabolome level the spectra obtained from ESI-MS/MS suggest that asterosaponins, bioactive secondary metabolites with known immunological, physiological and pharmacological activities, seem to be also promising actors in the regeneration process. Performance of future studies urge to clarify the importance of the detected molecular profile changes on regeneration and to depict the associated molecular and cellular mechanisms.