Dominant and recessive mutations in rhodopsin activate different cell death pathways

Mutations in rhodopsin (RHO) are a common cause of retinal dystrophy and can be transmitted by dominant or recessive inheritance. Clinical symptoms caused by dominant and recessive mutations in patients and animal models are very similar but the molecular mechanisms leading to retinal degeneration may differ. We characterized three murine models of retina degeneration caused by either Rho loss of function or expression of the P23H dominant mutation in Rho. Rho loss of function is characterized by activation of calpains and apoptosis-inducing factor (Aif) in dying photoreceptors. Retinas bearing the P23H dominant mutations activate both the calpain-Aif cell death pathway and ER-stress responses that together contribute to photoreceptor cell demise. In vivo treatment with the calpastatin peptide, a calpain inhibitor, was strongly neuroprotective in mice lacking Rho while photoreceptor survival in retinas expressing the P23H dominant mutation was more affected by treatment with salubrinal, an inhibitor of the ER-stress pathway. The further reduction of photoreceptor cell demise by co-treatment with calpastatin and salubrinal suggests co-activation of the calpain and ER-stress death pathways in mice bearing dominant mutations in the Rho gene

Shipwrecks stories in a “trap bay”: Research and valorization in Torre S. Sabina (Brindisi, Italy)

The 2020 underwater archaeological research in the inlet of Torre Santa Sabina - Baia dei Camerini (Municipality of Carovigno, Brindisi, Italy ) represented the first phase of the pilot intervention of the Interreg Italia-Croatia UnderwaterMuse project, which aims to enhance and make accessible the huge underwater heritage of the areas involved through the creation of submerged archaeological parks and the narrative and communicative use of the virtual reality. The Puglia Region - Department of Tourism, Economics of Culture and Valorization of the Territory, partner of the UnderwaterMuse project, launching these researches aimed at valorisation, has involved the three regional Universities thanks to an agreement. The fruitful synergy between the various actors involved and the support of the territory and the community have allowed the achievement of the objectives of this campaign, preliminary to the broader and more articulated intervention foreseen for the next year. Thanks to the collaboration with the Polytechnic of Turin, the entire stretch of coast was mapped with drone flights, in order to reconstruct the coastal landscape in the various phases, starting from the Bronze Age. Targeted interventions were carried out on the Roman wreck of the imperial age, beached and abandoned at the ancient shore and now submerged due to the relative rise in sea level, and on the remains of on-board equipment of a ship of the Serenissima, the Galea Magna (1598). Another important focus was represented by the stratigraphy of cargos resulting from the various shipwreck episodes, accumulated at the foot of the western cliff

Pigment epithelium-derived factor hinders photoreceptor cell death by reducing intracellular calcium in the degenerating retina

Abstract Calcium ions play a critical role in neuronal cell death. Pigment epithelium-derived factor (PEDF) is a promising neuroprotective protein for photoreceptor cells but the mechanisms mediating its effects against retinal degeneration are still not well characterized. We addressed this question in the rd1 degenerating mouse retina that bears a mutation in the Pde6b gene encoding one subunit of the phosphodiesterase enzyme. Loss of phosphodiesterase activity in rod photoreceptor cells increases cyclic guanosine monophosphate (cGMP) levels leading to a rise in intracellular calcium. Short-term treatments with recombinant human PEDF protein decreased intracellular calcium in photoreceptors in vivo. Taking advantage of calcium pump blockers, we defined that PEDF signaling acts on PMCA calcium pumps to lower intracellular calcium. PEDF restrained cell death pathways activated by high calcium levels and engaging calpains, BAX and AIF. The neurotrophic effects were mediated by the PEDF receptor (PEDF-R), encoded by the PNPLA2 gene. Finally, peptides containing the neurotrophic domain of PEDF targeted these same cell death pathways in vivo. The findings reveal rescue from death of degenerating photoreceptor cells by a PEDF-mediated preservation of intracellular calcium homeostasis

The “invisible” heritage to the challenge of the valorization: the UnderwaterMuse Project

The Adriatic sea is dotted with wrecks and its coasts are scattered by a lot of underwater sites. The routes, the types of hulls and their cargos, the different types of coastal sites in some cases have been well studied, in others only the coordinates are known. The UnderwaterMuse Project focuses on some of them, in order not only to increase knowledge, but above all to make them visitable by as many people and in different ways as possible, always paying the utmost attention to their integrity. The project aims at applying on sample areas (maritime landscapes of Torre Santa Sabina, Grado, Resnik / Siculi, Venice lagoon) a methodological and technological protocol based on research / knowledge and development / communication of underwater archeological sites that are complex, multi-stratified and characterized by strong diversity. The project’s objective is therefore to transform the site into an underwater archaeological park (or eco-museum) through innovative and / or experimental methodologies and techniques in order to try to reduce the loss of important cultural heritages as well as to guarantee an economic spin-off deriving directly from the creation of a sector linked to the tourist-cultural promotion of the context of reference. An immersive virtual reality (VR) approach renders underwater sites accessible to a wider public, including people with different kinds of disabilities. Training diving guides will improve the immersive experience of underwater sites. Based on the experience gained, an innovative promotional GIS tool, the ‘UnderwaterMuse MAP’ for promoting underwater sites with accessibility standards, will be developed. The ‘UnderwaterMuse MAP’ will be promoted at transnational, national and local level, in the Adriatic and beyond. Keywords: underwater cultural heritage, in situ protection and valorization, underwater archaeological park, VR, GIS

The Invisible Heritage and the Challenge of its Valorisation. The UnderwaterMuse Project.

The Adriatic sea is dotted with wrecks and its coasts are scattered by a lot of underwater sites. Some of these are well studied, of others only the coordinates are known. The UnderwaterMuse Project focuses on some of these, in order not only to increase knowledge, but above all to make them visitable by as many people and different ways as possible, always paying the utmost attention to their integrity. The project aims at applying on sample areas (maritime landscapes of Torre Santa Sabina, Grado, Resnik/Siculi, and Venice lagoon) a methodological and technological protocol based on research, knowledge and development, and communication of underwater archeological sites that is complex, multi-stratified and characterized by strong diversity. The project’s objective is therefore to transform the site into an underwater archaeological park (or eco-museum) through innovative and/or experimental methodologies and techniques in order to reduce the loss of important cultural heritages as well as to guarantee an economic spin-off deriving directly from the creation of a sector linked to the tourist-cultural promotion of the context of reference. Training diving guides will improve the immersive experience of underwater sites. Based on the experience gained, the GIS tool, the ‘UnderwaterMuse MAP’ for underwater sites with accessibility standards, will be developed and promoted at transnational, national and local level, in the Adriatic and beyond

Shipwreck Stories in a Trap Bay. Research and Valorisation in Torre Santa Sabina (Brindisi, Italy)

The underwater archaeological research in the inlet of Torre Santa Sabina – Baia dei Camerini (Muni - cipality of Carovigno, Brindisi, Italy) is the pilot intervention of the Interreg Italia-Croatia Under waterMuse project, which aims to enhance and make accessible the huge underwater cultural heritage of the areas involved through the creation of submerged archaeological parks and the narrative and communicative use of the virtual reality. The Puglia Region – Department of Tourism, Economy of Culture and Valorisation of the Territory, partner of the UnderwaterMuse project, has involved the three regional Universities thanks to an agreement. Their fruitful synergy and the support of the community have allowed the achievement of the objectives of the campaigns 2020– 2021. Thanks to the collaboration with the Polytechnic University of Turin, the entire stretch of coast was mapped with drone flights, in order to reconstruct the coastal landscape in its various phases, starting from the Bronze Age. Targeted interventions was carried out on a Roman Imperial wreck, beached and abandoned at the ancient shore and now submerged due to the relative rise in sea level, and on the remains of on-board equipment of a ship of the Venetian Serenissima, the GALEAMAGNA (1598). Another important focus was the stratigraphy of cargoes from various shipwrecks accumulated at the foot of the western cliff

Lateralized overgrowth with vascular malformation caused by a somatic PTPN11 pathogenic variant: another piece added to the puzzle of mosaic RASopathies

Lateralized/segmental overgrowth disorders (LOs) encompass a heterogeneous group of congenital conditions with excessive body tissue growth. Documented molecular alterations in LOs mostly consist of somatic variants in genes of the PI3KCA/AKT/mTOR pathway or of chromosome band 11p15.5 imprinted region anomalies. In some cases, somatic pathogenic variants in genes of the RAS/MAPK pathway have been reported. We present the first case of a somatic pathogenic variant (T507K) in PTPN11 causing a LO phenotype characterized by severe lateralized overgrowth, vascular proliferation, and cerebral astrocytoma. The T507K variant was detected in DNA from overgrown tissue in a leg with capillary malformation. The astrocytoma tissue showed a higher PTPN11 variant allele frequency. A pathogenic variant in FGFR1 was also found in tumor tissue, representing a second hit on the RAS/MAPK pathway. These findings indicate that RAS/MAPK cascade overactivation can cause mosaic overgrowth phenotypes resembling PIK3CA-related overgrowth disorders (PROS) with cancer predisposition and are consistent with the hypothesis that RAS/MAPK hyperactivation can be involved in the pathogenesis of astrocytoma. This observation raises the issue of cancer predisposition in patients with RAS/MAPK pathway gene variants and expands genotype spectrum of LOs and the treatment options for similar cases through inhibition of the RAS/MAPK oversignalling

The somatic p.T81dup variant in AKT3 gene underlies a mild cerebral phenotype and expands the spectrum including capillary malformation and lateralized overgrowth

Heterozygous germline or somatic variants in AKT3 gene can cause isolated malformations of cortical development (MCDs) such as focal cortical dysplasia, megalencephaly (MEG), Hemimegalencephaly (HME), dysplastic megalencephaly, and syndromic forms like megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome, and megalencephaly-capillary malformation syndrome. This report describes a new case of HME and capillary malformation caused by a somatic AKT3 variant that differs from the common p.E17K variant described in literature. The patient's skin biopsy from the angiomatous region revealed an heterozygous likely pathogenic variant AKT3:c.241_243dup, p.(T81dup) that may affect the binding domain and downstream pathways. Compared to previously reported cases with a common E17K mosaic variant, the phenotype is milder and patients showed segmental overgrowth, an uncommon characteristic in AKT3 variant cases. These findings suggest that the severity of the disease may be influenced not only by the level of mosaicism but also by the type of variant. This report expands the phenotypic spectrum associated with AKT3 variants and highlights the importance of genomic analysis in patients with capillary malformation and MCDs