Project description:The origin of cells involved in regeneration in Echinoderms is an open question till now. Most experimental data support the process of transdifferentiation as the main mechanism, although the activity of progenitor/stem cells is also considered. The renewal of coelomocytes, the cells which occupy the coelomic cavity in Asterias rubens is an example of physiological regeneration. Although it is considered that coelomic epithelium is the main source of coelomocytes, many details of this process remain unclear. In this study, we provide evidence of the origin of several types of coelomocytes in A. rubens from the coelomic epithelium, with particular emphasis on small undifferentiated cells. The concept of a pool of marginal coelomocytes is introduced as cells sequestered on the surface of the coelomic epithelium and characterized by a special cellular composition. Proteomic analysis by LC-MALDI TOF/TOF MS identified in total 403 proteins in coelomocytes (COE), coelomic epithelium (CE) and coelomic epithelium subpopulation enriched with undifferentiated cells (CEW). Proteins common and associated with each cell pool were revealed and the intermediate status of cells on the border of coelomic epithelium and coelom was confirmed. The potential players involved in regenerative processes were identified.
Project description:Echinoderms, possessing outstanding regenerative capability, provide unique model system for the study of the response to injury. However, there is little known about the proteomic composition of coelomic fluid, an important biofluid circulating through the whole body and reflecting an overall biological status of the organism. In this study, we used LC-MALDI tandem mass spectrometry to characterize proteome of cell-free coelomic fluid of starfish Asterias rubens and follow the changes occurring in response to puncture wound and blood loss. Our study demonstrated significant changes of CF proteome during the first hours after injury and presented a series of candidate proteins involved in early response to injury, providing interesting targets for future functional studies.