Proteomic analysis of injury-related changes in coelomic fluid of the common starfish Asterias rubens. Proteomics of starfish coelomic fluid

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. In total, 91 proteins were identified, of which 61 were extracellular soluble and 16 bound to plasma membrane. Most represented functional terms were “pattern recognition receptor activity” and “peptidase inhibitor activity”. Injury-responsive proteins were revealed: 33 were up-regulated in puncture wound and 41 in blood loss, with an overlap of 17 proteins. Ependymin, beta-microseminoprotein, serum amyloid A, and avidin-like proteins, involved in intestinal regeneration in sea cucumber, were also identified as injury-responsive proteins. Degradation of collagenous ECM as early as 6 hours after injury was detected. 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.