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Since 50's the scientific diving community has endeavoured to promote safe, effective diving through self-imposed training and education programs. In the last few decades in some countries the Government recognised peculiarity and requirements of scientific diving. In the year 20008, the Europaean Science Foundation adopted the Marine Board Europaean Scientific Diving Panel (ESDP). The main objectives of the ESDP are: i) to encourage international mobility in the Europaean scientific diving community through the implementation of a support framework ; ii) to promote safety in scientific divings across Europe ; iii) to advance underwater scientific excellence in Europe. Within the ESDP framework, the proposed ESDTN project will focus on the training of early-stage researches (ESRs) in the development and application of innovative underwater scientific methods and approaches in the fields of biology, experimental ecology, cartogaphy and human impact assessment. A limited number of experienced researchers (ERs) will be recruited to collaborate in research activities and complete their formation. ESRs and ERs will be trained to apply a range of underwater scientific methods, from measurements to manipulative field experiments, sharing competences from different fields and improving their skills. Each ESR should develop a 3-years research program in a specific scientific field increasing knowledge in natural and/or anthropogenic marine processes or developing new underwater methodologies or instruments. The trans-nationaljoint research training network will be based on Europaean universities with well established research and training experience in these fields, which can provide high-quality education and a mutually recognised PhD certificate. Associated partners will include national and international organizations and a number of small-medium enterprises (SMEs), which can provide research and complementary training and secondment opportunities.

In some sponges peculiar proteins called silicateins catalyze silica polymerization in ordered structures, and their study is of high interest for possible biotechnological applications in the nanostructure industry. In this work we describe the isolation and the molecular characterization of silicatein from spicules of Petrosia ficiformis, a common Mediterranean sponge, and the development of a cellular model (primmorphs) suitable for in vitro studies of silicatein gene regulation. The spicule of P. ficiformis contains an axial filament composed of 2 insoluble proteins, of 30 and 23 kDa. The 23-kDa protein was characterized, and the full-length cDNA was cloned. The putative amino acid sequence has high homology with previously described silicateins from other sponge species and also is very similar to cathepsins, a cystein protease family. Finally, P. ficiformis primmorphs express the silicatein gene, suggesting that they should be a good model for biosilicification studies.

Recently, the thermosensing pathway in sponges (Porifera) was elucidated. The thermosensor triggering this cascade is a heat-activated cation channel, with the phytohormone abscisic acid (ABA), cyclic ADP-ribose (cADPR) and calcium acting as intracellular messengers, similarly to the drought-stress signaling cascade in higher plants. Here, we investigated the functional effects downstream of the temperature-signaling pathway in Axinella polypoides (Porifera, Demonspongiae). Short-term stimulation followed by long-term depression of amino acid incorporation, oxygen consumption and water filtration were observed after exposure of the sponge to a brief heat stress or to micromolar ABA. These effects could be prevented by the targeted interruption of the signaling pathway either at the level of the cation channel thermosensor or at the level of the cADPR-induced intracellular calcium increase. Moreover, release of cyclase activity into the sea water and generation of extracellular cADPR were observed following brief heat stress. Intact sponge cells were sensitive to extracellular cADPR and addition of purified cyclase increased sponge respiration similarly to heat stress. This is the first observation of functional effects exerted on Metazoa by the phytohormone ABA: conservation of the ABA/cADPR stress-signaling cascade points to its early evolution in a common precursor of modern Metazoa and Metaphyta. The functional effects induced by extracellular cyclase/cADPR suggest an evolutionary origin of cADPR as an ancient stress hormone in Porifera.

Sponges are the most ancient known metazoans. Their cells are specialised but not organised into tissues or organs. Recordings of action potential-like propagating electrical impulses suggested that electrical signalling may occur between sponge cells, but the characterization of ionic channels in these cells is still at the beginning. Actually, sponge cell surfaces are covered by a complex glycocalyx and long-chain fatty acids are present in the lipid core of their membranes. In these experimental conditions, a low percentage of tight seals (3%) was obtained applying the patch-clamp technique to cells isolated from the Mediterranean Demospongia Axinella polypoides. This paper shows in detail how difficulties can be overcome making use of trivalent cations in the extracellular solution and how electrophysiological measurements can be performed on sponge cell membranes. A potassium selective conductance is shown as an example. We suggest that the presented methodology could also be applied to other cell types.