Role Of Gap Junction Intercellular Communications In Morphogenesis Of Basal Metazoa

The aim to study the role of Gap-Junction-mediated-intercellular-Communications(GJIC) and of retinoic-acid in the embryo-development and polyp-regeneration of the model Clava multicornis was achieved. Colonies of the roscoffensis ecotype of C.multicornis in very good condition were provided by Service-Mer-&-Observation of SBR. Animals were maintained in aquaria, in wet lab, and used for experiments. The GJ and RA roles were investigated by pharmacological-inhibition using GJ-inhibitors, RA and RA-inhibitors looking at: (i) morphogenesis and differentiation through embryonic and larval development; (ii) regeneration ability of amputee polyps considering the patterns of tissue reorganization; (iii) the specific behavior, gene and protein expression at the larval stage (samples were in vivo treated and stored for at home analyses); (iv) the putative presence of GJ-hemi-channels using GJ-permeant and –non-permeant fluorescent dyes and observation at confocal microscopy. Preliminary analysis showed that: a) not all GJ-inhibitors blockaded GJ-hemi-channels; b) GJ-inhibitors and RA can influences the regenerative capability of the polyps, inducing stolon-formation, whereas in control specimens prevalently tentacles and hypostome were regenerated. Information about the analysis of already obtained sequences (from the applicant) was obtained within a mini-project Assemble-Cnidaria in collaboration with ABIMS at the SBR. All the facilities were available during the on site research activity except the confocal microscopy. The in vivo experiments carried on site and the following analyses, as such as the comparison with previous data will allow us to clarify the GJIC mediated networking mechanisms and to shed light on such key mechanisms with high level of functional conservation from basal invertebrates to chordates.