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Polyhydroxybutyrate (PHB) is a biodegradable bio-based polymer synthesized by microorganisms under unfavorable conditions from agro-industrial residues as a source of carbon. These aspects make the bio-based polymer attractive for the mass production of biodegradable plastics, and a definitive replacement for petroleum-based plastics. The aim of this work was to characterize the putative PHB-producing bacterium 1B isolated from the argan soil, to identify the polymer produced, and quantify the PHB production using argan seeds waste. DNA extraction, PCR, and Sanger sequencing were conducted for the molecular identification of strain 1B; the residual biomass and the PHB quantification were measured and compared in the presence of simple sugars and pretreated argan seeds waste. The 1B growth and PHB synthesis were optimized by selecting physical and nutritional parameters: temperature, incubation time, pH, NaCl concentration, and nitrogen sources concentrations. A preliminary characterization of the bio-based polymer extracted was conducted by UV-Visible spectrophotometry and FTIR analysis. The strain 1B was identified as belonging to the genus Sphingomonas. The PHB final yield was higher in a growth culture enriched with argan waste (3.06%) than with simple sugars. The selected conditions for the bacterial optimal growth incremented the PHB final yield to 6.13%, while the increase in the argan residue concentration from 1 to 3% in a larger culture volume led to the PHB final yield of 8.16%. UV-Visible spectrophotometry of the extracted sample reported a remarkable peak at 248 nm, as well as FTIR spectra analysis, showed peaks at 1728 and 1282 wavenumber/cm. Both preliminary characterizations demonstrated that the extracted sample is the bio-based polymer polyhydroxybutyrate. The results reported in this work reveal how the costless available argan seeds can be used for polyhydroxybutyrate production using a novel Sphingomonas species.

The aim of this work was to study the valorization of argan seed pulp, a waste material obtained from argan oil extraction, for the biosynthesis of polyhydroxybutyrate (PHB). A new species that showed the metabolic capacity for the conversion of argan waste into the bio-based polymer was isolated from an argan crop located in Teroudant, a southwestern region of Morocco, where the arid soil is exploited for goat grazing. The PHB accumulation efficiency of this new species was compared to the previously identified species 1B belonging to the genus Sphingomonas, and results were reported as dry cell weight residual biomass and PHB final yield measured. Temperature, incubation time, pH, NaCl concentration, nitrogen sources, residue concentrations, and culture medium volumes were analyzed with the aim of obtaining a maximum accumulation of PHB. UV-visible spectrophotometry and FTIR analysis confirmed that PHB was present in the material extracted from the bacterial culture. The results of this wide investigation indicated that the new isolated species 2D1 had a higher efficiency in PHB production compared to the previously identified strain 1B, which was isolated from a contaminated argan soil in Teroudant. PHB final yield of the two bacterial species, i.e., the new isolated and 1B, cultivated under optimal culture conditions, in 500 mL MSM enriched with 3% argan waste, were 21.40% (5.91 ± 0.16 g/L) and 8.16% (1.92 ± 0.23 g/L), respectively. For the new isolated strain, the result of the UV-visible spectrum indicates the absorbance at 248 nm, while the FTIR spectrum showed peaks at 1726 cm−1 and 1270 cm−1: these characteristic peaks indicated the presence of PHB in the extract. The data from the species 1B UV-visible and FTIR spectra were previously reported and were used in this study for a correlation analysis. Furthermore, additional peaks, uncharacteristic of standard PHB, suggest the presence of impurities (e.g., cell debris, solvent residues, biomass residues) that persisted after extraction. Therefore, a further enhancement of the sample purification during extraction is recommended for more accuracy in the chemical characterization. If 470,000 tons of argan fruit waste can be produced annually, and 3% of waste is consumed in 500 mL culture by 2D1 to produce 5.91 g/L (21.40%) of the bio-based polymer PHB, it can be estimated that the amount of putative PHB that can be extracted annually from the total argan fruit waste is about 2300 tons.

Fragile X syndrome is a neuro-developmental disease affecting intellectual abilities and social interactions. Drosophila melanogaster represents a consolidated model to study neuronal pathways underlying this syndrome, especially because the model recapitulates complex behavioural phenotypes. Drosophila Fragile X protein, or FMRP, is required for a normal neuronal structure and for correct synaptic differentiation in both the peripheral and central nervous systems, as well as for synaptic connectivity during development of the neuronal circuits. At the molecular level, FMRP has a crucial role in RNA homeostasis, including a role in transposon RNA regulation in the gonads of D. m. Transposons are repetitive sequences regulated at both the transcriptional and post-transcriptional levels to avoid genomic instability. De-regulation of transposons in the brain in response to chromatin relaxation has previously been related to neurodegenerative events in Drosophila models. Here, we demonstrate for the first time that FMRP is required for transposon silencing in larval and adult brains of Drosophila “loss of function” dFmr1 mutants. This study highlights that flies kept in isolation, defined as asocial conditions, experience activation of transposable elements. In all, these results suggest a role for transposons in the pathogenesis of certain neurological alterations in Fragile X as well as in abnormal social behaviors.

In order to halt the loss of global biodiversity and considering the United Nations Decade for Ocean Conservation Agenda, increasing efforts to improve biomonitoring programs and assessment of ecosystem health are needed. Aquatic environments are among the most complex to monitor, requiring an array of tools to assess their status and to define conservation targets. Although several parameters need to be considered for a comprehensive ecological status assessment, it is important to identify easy-to-apply high-resolution monitoring methods. Shifts in fish composition and abundance are often good indicators of ecosystem health status in relation to anthropogenic activities. However, traditional monitoring methods are strictly related to the habitat under study and cannot be applied universally. This review summarizes the importance of ecological indicators for aquatic environments subjected to anthropogenic stressors, with a particular focus on fish communities and transitional water ecosystems. We describe the main characteristics of both traditional and novel methods for fish monitoring, highlighting their advantages and shortcomings in an attempt to identify simple and reliable ways for a correct evaluation of the dynamics of aquatic ecosystems.

The Mediterranean Sea is known for hosting a high diversity of species, with more than 17,000 reported marine species, one fifth which are endemic. Moreover, the number of non-indigenous species (NIS) in the Mediterranean Sea is recently reported to be increasing. The monitoring and the distribution of NIS is a key requirement for the conservation and management of the ecosystems, as also foreseen by the regulation (EU) No 1143/2014 of the European Parliament and of the Council of 22 October 2014 on the prevention and management of the introduction and spread of invasive alien species. A promising innovative approach for the identification of species and biodiversity is the use of molecular tools (DNA barcoding and metabarcoding). Combined with environmental DNA (eDNA) extracted from environmental samples like water or sediment, traces of species can be identified. Currently, the main limitation in the use of molecular tools (DNA barcoding and metabarcoding, eDNA) for species identification is the incompleteness of the DNA barcode reference databases. We assessed the extent of gaps in DNA barcode reference libraries, using the most updated inventory of 666 confirmed alien species occurring in the Mediterranean Sea. Also, the availability of primers for the amplification process was investigated. 32.58% of these species lack DNA barcodes in the reference libraries. Also, 70% of the retrieved NIS in the DNA barcode libraries lack the public availability of the primers used for the amplification process. The results of this study allow us to direct scientific efforts towards specific taxonomic groups in order to complete the NIS DNA barcode reference libraries and enable effective application of eDNA in investigations of the occurrence and the distribution of NIS in the Mediterranean Sea, and in the first sighting of still unknown NIS.

Simple Summary The biodiversity and ecological status assessment of transitional water ecosystems by benthic macroinvertebrates investigation could use DNA barcode tools for more rapid and efficient outputs. The principal limits of this application are the incompleteness of DNA barcode databases, the identification of optimal primers set, and the gap in the species sequences. The influence of the incompleteness of DNA barcode libraries on species diversity indices, ecological indicators, and ecological status assessment in transitional waters of the southeast Mediterranean were analysed, underlying the importance to implement DNA barcode libraries and to put an effort toward specific species at a local level. Abstract The ecological assessment of European aquatic ecosystems is regulated under the framework directives on strategy for water and marine environments. Benthic macroinvertebrates are the most used biological quality element for ecological assessment of rivers, coastal-marines, and transitional waters. The morphological identification of benthic macroinvertebrates is the current tool for their assessment. Recently, DNA-based tools have been proposed as effective alternatives. The main current limits of DNA-based applications include the incompleteness of species recorded in the DNA barcode reference libraries and the primers bias. Here, we analysed the influence of the incompleteness of DNA barcode databases on species diversity indices, ecological indicators, and ecological assessment in transitional waters of the southeast Mediterranean, taking into account the availability of commonly sequenced and deposited genomic regions for listed species. The ecological quality status assigned through the potential application of both approaches to the analysed transitional water ecosystems was different in 27% of sites. We also analysed the inter-specific genetic distances to evaluate the potential application of the DNA metabarcoding method. Overall, this work highlights the importance to expand the barcode databases and to analyse, at the regional level, the gaps in the DNA barcodes.

The loss of aquatic biodiversity is increasing at a rapid rate globally. There is a worldwide effort to protect, preserve and restore aquatic ecosystems. For efficient biodiversity monitoring and reliable management tools, comprehensive biodiversity data are required. The abundance and species diversity of benthic macroinvertebrates are commonly used as indicators of the aquatic ecosystem condition. Currently, macroinvertebrate species biodiversity assessment is based on morpho-taxonomy, which could be enhanced by recent advances in DNA-based tools for species identification. In particular, DNA metabarcoding has the potential to identify simultaneously many different taxa in a pool of species and to improve aquatic biomonitoring significantly, especially for indicator species. This review is focused on the current state of DNA-based aquatic biomonitoring using benthic macroinvertebrates in the Mediterranean region.

Summary: Chromatin organization plays a crucial role in tissue homeostasis. Heterochromatin relaxation and consequent unscheduled mobilization of transposable elements (TEs) are emerging as key contributors of aging and aging-related pathologies, including Alzheimer’s disease (AD) and cancer. However, the mechanisms governing heterochromatin maintenance or its relaxation in pathological conditions remain poorly understood. Here we show that PIN1, the only phosphorylation-specific cis/trans prolyl isomerase, whose loss is associated with premature aging and AD, is essential to preserve heterochromatin. We demonstrate that this PIN1 function is conserved from Drosophila to humans and prevents TE mobilization-dependent neurodegeneration and cognitive defects. Mechanistically, PIN1 maintains nuclear type-B Lamin structure and anchoring function for heterochromatin protein 1α (HP1α). This mechanism prevents nuclear envelope alterations and heterochromatin relaxation under mechanical stress, which is a key contributor to aging-related pathologies.

DNA metabarcoding for the identification of species and ecosystem biomonitoring is a promising innovative approach. The applicability of this tool is at first dependent on the coverage of the DNA sequence reference libraries. We performed a gap analysis of available DNA barcodes in the international databases using the aquatic macroinvertebrate species checklist of the Apulia region in southeast Italy. Our analyses show that 42% of the 1546 examined species do not have representative DNA barcodes in the reference libraries, indicating the importance of working toward their completeness and addressing this effort toward specific taxonomic groups in particular at local/regional level. The DNA-barcode coverage also varies among different taxonomic groups and aquatic ecosystem types in which a large number of species are rare. We also analyzed the DNA barcode reference libraries for the primer set used to barcode species. Only for 52% of the examined barcoded species were the primers reported, indicating the importance of uploading this information in the databases for a more extensive use of the DNA metabarcoding. We also highlighted the opportunity to develop combinations of primers useful at the regional level. We tested the application of the DNA barcoding single species to a lagoon ecosystem (the lagoon named “Aquatina di Frigole” in the Apulia region) which are richer in humic substances than other aquatic environments and in which DNA metabarcoding remains under explored.

The main objective of the project Common strategies and best practices to IMprove the transnational PRotection of ECOsystem integrity and services - IMPRECO is to enhance the safeguarding of ecosystems and ecosystem services. Additionally, the aim of this project is to tackle their environmental vulnerability by strengthening the potential of the Protected Areas in biodiversity, ecosystems and ecosystem services conservation. This is expected to be addressed by maintaining it through their transnational networking located in the European Adriatic-Ionian Macro-Region. The aim of this research is: 1) to characterise the habitats and ecosystems involved in the coastal-marine protected areas considered; 2) to set a biodiversity baseline; 3) to understand what current ecosystems’ conditions are; 4) to build up a transnational biomonitoring programme of target species and habitats and 5) to assess their response to pilot actions. To do so, a transnational inventory of species, habitats, ecosystems and ecosystem services was established, starting with the seven coastal-marine protected areas involved in the project. Data collection was carried out using different sources of information: scientific literature, officially available data from NATURA 2000 Standard Data Forms, checklists from local biomonitoring programmes, personal observations and citizen science, historical maps and data from new in-field analyses. Data were filled in the transnational biodiversity geo-databases according to the NATURA 2000 standards about habitat features, species protection level and species features. The presence of alien species (non-indigenous species, NIS) was also acknowledged and references about data collection were provided in the databases according to the Darwin Core standards.

Bio-based plastics, i.e., non-synthetic polymers produced from renewable resources are gaining special attention as a feasible solution to the environmental issues caused by concerns regarding the impact of waste plastics. Furthermore, such materials can also represent an alternative to petroleum-derived polymers, due to the scarcity of this raw material in the near future. In the polyhydroxyalkanoates (PHA) family, polyhydroxybutyrate (PHB) was the first to be synthesized and characterized. PHB soon gained great attention from industrial and academic researchers since it can be synthesized from a wide variety of available carbon sources, such as agro-industrial and domestic wastes. The aim of this original research has been the identification of the presence of PHB synthetizing bacteria in some soils in a Moroccan region and the production of the bio-based PHB. In particular, the soils of the argan fields in Taroudant were considered. Taroudant is a southwestern region of Morocco where the argan oil tree Argania spinosa is an endemic and preserved species. Starting from rhizospheric soil samples of an argan crop area, we isolated heat-resistant bacteria and obtained pure cultures from it. These bacteria present intracellular endospores stained by the Schaeffer-Fulton method. The presence of intracellular endospores is a very important starting point to verify the effective production of PHB as a compartmentalized material. Further analyses are currently ongoing to try to extract and characterize PHB granules.

The Mediterranean monk seal Monachus monachus (Hermann, 1779) is the most endangered pinniped in the world. In addition, its presence has not been documented for about two decades in the Apulian Region and about 10 years along the Italian coastline. In this work, we aim to describe an exceptional and well-documented observation of a subadult specimen of Monachus monachus occurring during the last days of January 2020 in the Salento peninsula (Apulia Region, Italy) for the first time after two decades of local extinction in the south-western Adriatic Sea.

Macroinvertebrates are commonly applied for ecological investigations and as ecological indicators. However, the role of the sampling technique, effort and habitat on macroinvertebrate descriptors, diversity indices and ecological indicators in transitional water ecosystems is little known yet. This research aims to evaluate the influence of sampling techniques on macroinvertebrate assemblages and ecological indicators comparing box-corer and litterbag techniques, in prairie and unvegetated habitats. The experiment was conducted in a protected Mediterranean shallow lagoon dominated by marine water input. Three types of litterbags were prepared with: i. Phragmites australis dry leaves (terrestrial input); ii. Posidonia oceanica dry leaves (marine input), and iii. an equal mixture of both leaves. Three replicates of box-corer samples were collected in two sites per habitat, litterbags were submerged and retrieved after 30 days. Macroinvertebrate abundance, species richness, diversity indices and ecological indicators were measured and compared among sampling techniques and between habitats. Macroinvertebrate data was then pooled, analysed and compared to each single technique. Twenty-seven species were sampled overall, 4 species overlapped between box-corer and litterbags, 6 species (26%) were exclusive to the box-corer and 16 species (59%) were caught using only litterbags. Species diversity in litterbags was always higher than in box-corer, but macroinvertebrate assemblages were described better when using data pooled. In prairie, the ecological indicators varied significantly between the data pooled and separate sampling technique. Finally, this research highlights the relevance of using more than one sampling technique to obtain a better description of macroinvertebrate assemblages and the ecological status of Mediterranean lagoons.

The environmental issues caused by the impacts of synthetic plastics use and derived wastes are arising the attention to bio-based plastics, natural polymers produced from renewable resources, including agricultural, industrial, and domestic wastes. Bio-based plastics represent a potential alternative to petroleum-based materials, due to the insufficient availability of fossil resources in the future and the affordable low cost of renewable ones that might be consumed for the biopolymer synthesis. Among the polyhydroxyalkanoates (PHA), the polyhydroxybutyrate (PHB) biopolymer has been synthesized and characterized with great interest due to its wide range of industrial applications. Currently, a wide number of bacterial species from soil, activated sludge, wastewater, industrial wastes, and compost have been identified as PHB producers. This work has the purpose of isolating and characterizing PHB-producing bacteria from the agricultural soil samples of Argania spinosa in the south region of Morocco where the plant species is endemic and preserved. During this research, four heat-resistant bacterial strains have been isolated. Among them, two species have been identified as endospore forming bacteria following the Schaffer-Fulton staining method with Malachite green and the Methylene blue method. Black intracellular granules have been appreciated in microscopy at 100× for both strains after staining with Sudan black B. The morphological and biochemical analyses of the isolates, including sugar fermentation and antibiotic susceptibility tests, preliminarily identified the strains 1B and 2D1 belonging to the genus Serratia and Proteus, respectively.

Circadian clocks control and synchronize biological rhythms of several behavioral and physiological phenomena in most, if not all, organisms. Rhythm generation relies on molecular auto-regulatory oscillations of interlocked transcriptional-translational feedback loops. Rhythmic clock-gene expression is at the base of rhythmic protein accumulation, though post-transcriptional and post-translational mechanisms have evolved to adjust and consolidate the proper pace of the clock. In Drosophila, BELLE, a conserved DEAD-box RNA helicase playing important roles in reproductive capacity, is involved in the small RNA-mediated regulation associated to the piRNA pathway. Here, we report that BELLE is implicated in the circadian rhythmicity and in the regulation of endogenous transposable elements (TEs) in both nervous system and gonads. We suggest that BELLE acts as important element in the piRNA-mediated regulation of the TEs and raise the hypothesis that this specific regulation could represent another level of post-transcriptional control adopted by the clock to ensure the proper rhythmicity.

Fragile-X Syndrome represents the most common form of hereditary mental retardation. The disorder originates with mutations in the Fmr1 gene coding for the FMRP protein, which, with its paralogs FXR1 and FXR2, constitute a well-conserved family of RNA-binding proteins. The dFmr1 gene is the Drosophila ortholog of the human gene (Fmr1) involved in the syndrome (1). Drosophila melanogaster is considered a good model for the study of the molecular mechanism at the bases of the different phenotypes exhibited by patients. Drosophila has a unique fragile X-related gene, the dFmr1 gene, whose mutants exhibit defects in neuronal structure and function, behavior, and germline development, resembling those observed in patients (2,3). During the first part of the project, we identified and validated a new role for the dFmr1 gene in the silencing of transposable elements and repetitive sequences mediated by the piRNA pathway in the gonads (2,4-6). The starting point was the observation that the crystal-Stellate interaction (2), depending on a correct function of the piRNA pathway, was deregulated in dFmr1 mutants. We also demonstrated that dFmr1 interacts genetically and co-localizes with Aubergine and Vasa, two key components of the pathway. We also investigated in detail the genetic and physical interaction of dFmr1 in gonads, looking at the rescue of the “crystal phenotype” in testes and at the fertility of dFmr1 mutants in a genetic background overexpressing genes with a role in the piRNA pathway. These results will be useful for clarifying the role of dFmr1 in gonads and even in the nervous system (6-8). During the last part of the project we analyzed the possible role of the piRNA pathway in the nervous system, gaining information on its presence in this tissue and on the function of dFmr1 in the pathway. In addition, we started studying a possible physiological role of transposable elements during the brain development. Our research intends to clarify if a common molecular base is involved in the majority of the phenotypes exhibited by dFmr1 mutants due to genome instability.

The eukaryotic porin, also called the Voltage Dependent Anion-selective Channel (VDAC), is the main pore-forming protein of the outer mitochondrial membrane. In Drosophila melanogaster, a cluster of genes evolutionarily linked to VDAC is present on chromosome 2L. The main VDAC isoform, called VDAC1 (Porin1), is expressed from the first gene of the cluster. The porin1 gene produces two splice variants, 1A-VDAC and 1B-VDAC, with the same coding sequence but different 5′ untranslated regions (UTRs). Here, we studied the influence of the two 5′ UTRs, 1A-5′ UTR and 1B-5′ UTR, on transcription and translation of VDAC1 mRNAs. In porin-less yeast cells, transformation with a construct carrying 1A-VDAC results in the expression of the corresponding protein and in complementation of a defective cell phenotype, whereas the 1B-VDAC sequence actively represses VDAC expression. Identical results were obtained using constructs containing the two 5′ UTRs upstream of the GFP reporter. A short region of 15 nucleotides in the 1B-5′ UTR should be able to pair with an exposed helix of 18S ribosomal RNA (rRNA), and this interaction could be involved in the translational repression. Our data suggest that contacts between the 5′ UTR and 18S rRNA sequences could modulate the translation of Drosophila 1B-VDAC mRNA. The evolutionary significance of this finding is discussed.

Visitare la Laguna di Acquatina, localizzata lungo la costa Adriatica del Salento, è un’esperienza sensoriale straordinaria, ricca di emozioni, che permette agli studiosi e a differenti gruppi di stakeholder di conoscere e apprezzare un patrimonio naturale dal valore inestimabile, di percepire i suoni dell’ambiente circostante e di osservare la biodiversità nelle sue molteplici forme. Fra queste, la biodiversità in specie è l’insieme delle specie animali, vegetali e microorganismi che si trovano in un ecosistema, in un habitat o in un’area predefinita. Le liste di specie, o checklist, sono gli strumenti di indagine con cui i ricercatori analizzano le variazioni della biodiversità in specie nel tempo, nello spazio e in relazione a differenti fattori di perturbazione, naturali e antropici, inclusi i cambiamenti climatici. Nella Laguna di Acquatina si può facilmente osservare anche la biodiversità a un livello di organizzazione ecologica superiore, cioè la biodiversità tra gli habitat. Quest’ultima è definita come l’eterogeneità degli habitat presenti in un ecosistema o in un’area predefinita. Ad Acquatina è facile osservare e individuare distintamente l’habitat acquatico, la macchia mediterranea, il cordone dunale, l’antistante spiaggia e il mare. La biodiversità in specie della Laguna di Acquatina è elevata, caratterizzata dalla presenza di tutti i gruppi tassonomici caratteristici degli ecosistemi acquatici di transizione e costieri dell’Ecoregione Mediterranea. Sono anche numerose le specie di interesse prioritario, cioè quelle specie che a seguito di forti minacce di degrado ed estinzione vengono sottoposte a un regime di tutela straordinario da parte delle istituzioni internazionali, europee e nazionali. A causa della presenza di numerose specie e habitat di interesse prioritario, la Laguna di Acquatina è inserita all’interno di un più ampio sito facente parte della Rete NATURA 2000. La Rete NATURA 2000 è stata istituita dall’Unione Europea e ha la finalità di tutelare e conservare le specie e gli habitat di interesse prioritario. L’ultimo censimento ufficiale relativo al 2015 elenca 33 specie di interesse prioritario per il sito NATURA 2000 denominato Aquatina di Frigole (IT9150003). La maggior parte delle specie riportate nel censimento appartengono all’avifauna, ma Pinna nobilis (Linnaeus, 1758) non era presente nel censimento del 2015. A partire dalla seconda metà del 2017, le attività didattiche, anche di rilievo internazionale, e di ricerca scientifica a carattere ecologico si sono rafforzate. La Laguna di Acquatina si è trasformata in un autentico laboratorio su campo, utile anche per azioni di divulgazione scientifica e di promozione degli sport acquatici ecosostenibili. Alla fine del 2017 sono stati rinvenuti i primi esemplari di Pinna nobilis (L.) durante lo svolgimento di un campionamento scientifico. Si tratta di un mollusco bivalve appartenente alla famiglia “Pinnidae”, comunemente chiamato cozza penna, nacchera o stura. Pinna nobilis è una specie endemica del Mar Mediterraneo, in cui è il più grande bivalve raggiungendo dimensioni anche superiori a un metro di lunghezza. È una specie protetta dall’Unione Europea attraverso le Direttive 92/43/CEE e 2006/105/CE. La pesca e la rimozione sono assolutamente vietate, e sono previste ingenti ammende per chi agisce illegalmente. Usualmente Pinna nobilis viene associata ad ambienti marini, essa vive sepolta per circa un terzo della sua lunghezza nel sedimento, tipicamente in fondi mobili, preferenzialmente associata alle praterie di fanerogame marine (Posidonia oceanica, Cymodocea nodosa e Zostera marina), e anche in zone sabbiose prive di vegetazione. Le pareti esterne delle valve vengono colonizzate da numerose specie incrostanti animali e vegetali, ciò contribuisce a incrementare la biodiversità in specie dell’area in cui si trova P. nobilis. Questa specie può anche colonizzare le porzioni più prossimali e protette di lagune e stagni costieri, in cui può costituire popolazioni ad elevata densità. Gli ambienti lagunari costituiscono, infatti, un “cosmo” singolarmente variegato ed attraente, per la complessità dei fattori ed interazioni ecologiche, e per la varietà di condizioni trofiche e climatiche che, nel complesso, favoriscono la colonizzazione di questi ambienti da parte di specie marine e d’acqua dolce, siano esse indigene o aliene. Per le sue caratteristiche ecologiche, Pinna nobilis è una specie utilizzata nel biomonitoraggio degli ecosistemi acquatici costieri, inclusi quelli marini, e come specie target nella Strategia Marina (Direttiva MSFD 2008/56/EC). Per quanto riguarda il suo ruolo ecologico, P. nobilis è una specie “filtratrice”- e fornisce numerosi servizi ecosistemici: filtra dalla colonna d’acqua una grande quantità di materia organica e detriti sospesi contribuendo alla rimozione dei nutrienti e alla trasparenza dell’acqua; ospita altre specie determinando un aumento della biodiversità locale; attira subacquei e snorkeler incentivando le attività ricreative e di educazione ambientale. Essendo una specie commestibile, già gli Egizi, i Romani e alcuni popoli Islamici utilizzavano questa specie per scopi alimentari, tessevano il suo bisso per fare dei pregiati ricami e lavoravano le valve per ottenere preziosi ornamenti per le loro vesti. A scala Mediterranea, le informazioni e la letteratura scientifica più recenti su Pinna nobilis (L.) ci raccontano, invece, di una specie esposta a numerose minacce di degrado, di una progressiva riduzione della densità di popolazione e scomparsa dovute alla pesca illegale, ai cambiamenti climatici, agli ancoraggi delle imbarcazioni da turismo e all’azione di un protozoo parassita, denominato Haplosporidium pinnae, che induce la morte degli organismi. La presenza di Pinna nobilis (L.) nella Laguna di Acquatina, Sito di Interesse Comunitario appartenente alla Rete NATURA 2000, sembra essere in controtendenza rispetto alla situazione attuale della specie. Probabilmente la laguna è utilizzata come nursery o habitat rifugio, avendo le condizioni ecologiche ottimali per la specie (Marrocco et al., 2018). L’indagine preliminare a cui si riferisce la ricerca è stata effettuata in un’area limitata della laguna, in vicinanza della foce, e ha permesso di individuare la presenza di undici individui, orientati verso la direzione Nord-Est. I principali parametri biometrici sono stati rilevati in ciascun individuo secondo il seguente schema. La larghezza massima e minima al fondo erano di 15,16 cm ± 0,726 e di 13,81 cm ± 0,611 rispettivamente, e la lunghezza della valva non coperta dal sedimento era di 16,66 cm ± 0,441. Il campionamento è stato “non distruttivo” e nessun individuo è stato rimosso o manipolato. Sono stati anche registrati i parametri abiotici della colonna d’acqua nella zona in cui P. nobilis è stata rilevata (temperatura 12,69 °C ± 0,207; ossigeno disciolto 7,21 mg*l-1 ± 0,278; salinità 24,77 PSU ± 0,963, pH 7,73 ± 0,084) (Marrocco et al., 2018). Benché si tratti di una indagine preliminare, ipotizziamo che la Laguna di Acquatina rappresenti un ambiente protetto per questa specie; qui potrebbe raggiungere dimensioni numeriche tali da permettere il reclutamento e il trans-planting in altri siti idonei, e quindi agevolarne il ripopolamento e la diffusione. La scoperta, effettuata da un team di ricercatori e studenti italiani e stranieri, provenienti da alcuni Paesi asiatici partecipanti al progetto INTER-ASIA, ha suggerito di approfondire l’attività di ricerca, di comunicazione scientifica e di citizen science nell’ambito del progetto IMPRECO “Common strategies and best practices to IMprove the transnational PRotection of ECOsystem integrity and services” – finanziato nell’ambito del Programma di Cooperazione Territoriale Europea “ADRION Adriatic-Ionian Programme INTERREG V-B Transnational 2014-2020, 1st call”. In particolare la ricerca è finalizzata al monitoraggio della specie su una scala spaziale che coinvolge il Mar Adriatico, Ionio ed Egeo. Infatti grazie alla partnership del progetto IMPRECO, distribuita nell’area di riferimento della Strategia Europea per la Regione Adriatico-Ionica (EUSAIR), sarà possibile avviare lo studio della dinamica di popolazione di Pinna nobilis, delle risposte alle perturbazioni e pressioni antropiche, ed ai parassiti mortali. Un protocollo di monitoraggio congiunto e semplificato (Joint Monitoring Protocol of IMPRECO) permetterà di raccogliere dati utili per la conservazione di Pinna nobilis su una ampia scala spaziale, e di coinvolgere gruppi interessati di stakeholder e cittadini nella raccolta dei dati e nella salvaguardia della specie. Per la sua rilevanza scientifica, la ricerca è stata recentemente pubblicata sulla rivista scientifica internazionale Nature Conservation (Marrocco et al., 2018).

The YAP and TAZ mediators of the Hippo pathway (hereafter called YAP/TAZ) promote tissue proliferation and organ growth. However, how their biological properties intersect with cellular metabolism remains unexplained. Here, we show that YAP/TAZ activity is controlled by the SREBP/mevalonate pathway. Inhibition of the rate-limiting enzyme of this pathway (HMG-CoA reductase) by statins opposes YAP/TAZ nuclear localization and transcriptional responses. Mechanistically, the geranylgeranyl pyrophosphate produced by the mevalonate cascade is required for activation of Rho GTPases that, in turn, activate YAP/TAZ by inhibiting their phosphorylation and promoting their nuclear accumulation. The mevalonate-YAP/TAZ axis is required for proliferation and self-renewal of breast cancer cells. In Drosophila melanogaster, inhibition of mevalonate biosynthesis and geranylgeranylation blunts the eye overgrowth induced by Yorkie, the YAP/TAZ orthologue. In tumour cells, YAP/TAZ activation is promoted by increased levels of mevalonic acid produced by SREBP transcriptional activity, which is induced by its oncogenic cofactor mutant p53. These findings reveal an additional layer of YAP/TAZ regulation by metabolic cues.

Eukaryotic porins or VDACs are a class of transmembrane proteins mainly localized in the outer mitochondrial membrane, whose function is to allow the diffusion of metabolites between the cytosol and the mitochondrion. In Drosophila melanogaster, as in other organisms, a small family of genes encoding porins has been discovered from the sequence of the genome. It is of general interest to understand whether these genes represent functional entities or not, and whether their product is associated to any particular tissue. In previous work we reported about the transcriptional and translational analysis of porin 1 and porin 2, and we proposed the specific presence of the latter in spermatozoa of the fly. In this paper we performed real time RT-PCR quantification of porin 1 and porin 2 transcripts in germ cells of the fly. It indicates that Porin 1 is abundantly expressed in both male and female tissues; Porin 2 instead, is very abundant in testis and it is present in ovaries as well, but in a small amount. The immuno-histological stain of ovaries shows that Porin isoform 1 is selectively targeted to follicular cells while Porin isoform 2 is present in mitochondria of the epithelial sheath cells of the ovariole. The implications of the subcellular distribution of these porin isoforms and the specific localization in germ tissues are discussed.

RNA metabolism controls multiple biological processes, and a specific class of small RNAs, called piRNAs, act as genome guardians by silencing the expression of transposons and repetitive sequences in the gonads. Defects in the piRNA pathway affect genome integrity and fertility. The possible implications in physiopathological mechanisms of human diseases have made the piRNA pathway the object of intense investigation, and recent work suggests that there is a role for this pathway in somatic processes including synaptic plasticity. The RNA-binding fragile X mental retardation protein (FMRP, also known as FMR1) controls translation and its loss triggers the most frequent syndromic form of mental retardation as well as gonadal defects in humans. Here, we demonstrate for the first time that germline, as well as somatic expression, of Drosophila Fmr1 (denoted dFmr1), the Drosophila ortholog of FMRP, are necessary in a pathway mediated by piRNAs. Moreover, dFmr1 interacts genetically and biochemically with Aubergine, an Argonaute protein and a key player in this pathway. Our data provide novel perspectives for understanding the phenotypes observed in Fragile X patients and support the view that piRNAs might be at work in the nervous system.

The crystal–Stellate system is one of the most known example of interaction between heterochromatin and euchromatin: a heterochromatic locus on the Y chromosome (crystal) 'represses’ a euchromatic locus (Stellate) on the X chromosome in Drosophila melanogaster. The molecular mechanism regulating this interaction is not completely understood. It is becoming clear that an RNA interference (RNAi) mechanism could be responsible for the silencing carried out by crystal on the Stellate sequences. Here, a detailed structural analysis of all the sequences involved in the system is reported, demonstrating a their 'puzzling’ structure. In addition three autosomal mutations: sting, scratch and sirio are described that interfere with the system. All of them are male sterile mutations and exhibit crystals made by the STELLATE protein in their primary spermatocytes. They are requested during oogenesis and early in embryogenesis as well. Hypothesis on the involvement of these genes in activating the Stellate sequences are discussed.

Pol32 is an accessory subunit of the replicative DNA Polymerase delta and of the translesion Polymerase zeta. Pol32 is involved in DNA replication, recombination and repair. Pol32's participation in high-and low-fidelity processes, together with the phenotypes arising from its disruption, imply multiple roles for this subunit within eukaryotic cells, not all of which have been fully elucidated. Using pol32 null mutants and two partial loss-of-function alleles pol32(rd1) and pol32(rds) in Drosophila melanogaster, we show that Pol32 plays an essential role in promoting genome stability. Pol32 is essential to ensure DNA replication in early embryogenesis and it participates in the repair of mitotic chromosome breakage. In addition we found that pol32 mutantssuppress position effect variegation, suggesting a role for Pol32 in chromatin architecture.

Fragile-X syndrome is the most common form of inherited mental retardation accompanied by other phenotypes, including macroorchidism. The disorder originates with mutations in the Fmr1 gene coding for the FMRP protein, which, with its paralogs FXR1 and FXR2, constitute a well-conserved family of RNA-binding proteins. Drosophila melanogaster is a good model for the syndrome because it has a unique fragile X-related gene: dFmr1. Recently, in addition to its confirmed role in the miRNA pathway, a function for dFmr1 in the piRNA pathway, operating in Drosophila gonads, has been established. In this review we report a summary of the piRNA pathways occurring in gonads with a special emphasis on the relationship between the piRNA genes and the crystal-Stellate system; we also analyze the roles of dFmr1 in the Drosophila gonads, exploring their genetic and biochemical interactions to reveal some unexpected connections.

International audience; The mechanisms of biological evolution have always been, and still are, the subject of intense debate and modeling. One of the main problems is how the genetic variability is produced and maintained in order to make the organisms adaptable to environmental changes and therefore capable of evolving. In recent years, it has been reported that, in flies and plants, mutations in Hsp90 gene are capable to induce, with a low frequency, many different developmental abnormalities depending on the genetic backgrounds. This has suggested that the reduction of Hsp90 amount makes different development pathways more sensitive to hidden genetic variability. This suggestion revitalized a classical debate around the original Waddington hypothesis of canalization and genetic assimilation making Hsp90 the prototype of morphological capacitor. Other data have also suggested a different mechanism that revitalizes another classic debate about the response of genome to physiological and environmental stress put forward by Barbara McClintock. That data demonstrated that Hsp90 is involved in repression of transposon activity by playing a significant role in piwi-interacting RNA (piRNAs)-dependent RNA interference (RNAi) silencing. The important implication is that the fixed phenotypic abnormalities observed in Hsp90 mutants are probably related to de novo induced mutations by transposon activation. In this case, Hsp90 could be considered as a mutator. In the present theoretical paper, we discuss several possible implications about environmental stress, transposon, and evolution offering also a support to the concept of evolvability.

Magnetic field effects are diffused among living organisms. They are mainly studied with static or extremely low frequency fields, while scarce information is available for pulsed fields. This work is devoted to the study of the interaction between Drosophila melanogaster, both adults and larvae, and pulsed magnetic fields. We exposed the organisms to a peak field of 0.4 T, lasting for about 2 μ s, within an ad hoc designed copper coil. Adult individuals didn't present any deregulation of repetitive sequences in the germ line of Drosophila. Instead, we noticed a marked magnetic field effect in larvae. Polytene chromosomes coming from treated individuals showed the presence of heat shock puffs; the same organisms revealed also an upregulation of the genes encoding for the Hsp70 protein. These observations suggest that the larvae underwent an oxidative stress caused by the modulation of free radicals' yield induced by the magnetic field through a radical pair mechanism.

The Stellate-made crystals formation in spermatocytes is the phenotypic manifestation of a disruptedcrystal-Stellateinteraction in testes ofDrosophila melanogaster. Stellatesilencing is achieved by the piRNA pathway, but many features still remain unknown. Here we outline the important role of thecrystal-Stellatemodifiers. These have shed light on the piRNA pathways that defend genome integrity against transposons and other repetitive elements in the gonads. In particular, we illustrate the finding that HSP90 participates in the molecular pathways of piRNA production. This observation has relevance for the mechanisms underlying the evolutionary canalization process.

It has been suggested that the molecular chaperone protein Hsp90 (heat shock protein 90) is part of an evolutionarily conserved buffering mechanism that preserves the development process from phenotypic variance despite genetic and environmental perturbation. Specchia et al. offer an additional or an alternative mechanism whereby Hsp90 influences phenotypic variation by affecting the piRNA silencing mechanism leading to transposon activation. Phenotypic robustness in the face of genetic and environmental perturbations — known as canalization — relies on buffering mechanisms. Hsp90 chaperone machinery has been proposed to be an evolutionarily conserved buffering mechanism of phenotypic variance. Here, an additional, perhaps alternative, mechanism whereby Hsp90 influences phenotypic variation is proposed; Hsp90 mutations can generate new variation by transposon-mediated mutagenesis. The canalization concept1 describes the resistance of a developmental process to phenotypic variation, regardless of genetic and environmental perturbations, owing to the existence of buffering mechanisms. Severe perturbations, which overcome such buffering mechanisms, produce altered phenotypes that can be heritable and can themselves be canalized by a genetic assimilation process. An important implication of this concept is that the buffering mechanism could be genetically controlled. Recent studies on Hsp90, a protein involved in several cellular processes and development pathways2,3,4,5, indicate that it is a possible molecular mechanism for canalization and genetic assimilation. In both flies and plants, mutations in the Hsp90-encoding gene induce a wide range of phenotypic abnormalities, which have been interpreted as an increased sensitivity of different developmental pathways to hidden genetic variability6,7. Thus, Hsp90 chaperone machinery may be an evolutionarily conserved buffering mechanism of phenotypic variance, which provides the genetic material for natural selection. Here we offer an additional, perhaps alternative, explanation for proposals of a concrete mechanism underlying canalization. We show that, in Drosophila, functional alterations of Hsp90 affect the Piwi-interacting RNA (piRNA; a class of germ-line-specific small RNAs) silencing mechanism leading to transposon activation and the induction of morphological mutants. This indicates that Hsp90 mutations can generate new variation by transposon-mediated ‘canonical’ mutagenesis.

The crystal-Stellate system is one of the best-known examples of heterochromatin-euchromatin interaction. The components of this system are homologous repetitive sequences clustered in three regions: 12E1 and h27 on the X and h11 on the Y. The symptom of a disrupted crystal-Stellate interaction is the presence of crystals in the spermatocytes of males lacking the crystal region. Stellate silencing is based on the RNAi process. Many modifiers of this system have been isolated and many of these are involved in RNAi. One of these modifiers is aubergine(sting); this is a "gain of function" allele in somatic tissues. Here we report the different behavior of two aubergine alleles with respect to the RNAi pathway: aub(sting) and a "loss of function" heteroallelic combination aub(HN)/aub(QC42). An increased amount of Aub interferes with the correct functioning of the somatic yellow hairpin RNAi, whereas the Aub reduction does not. We also demonstrate the different behavior of these alleles on the I transposon silencing in ovaries. Intriguingly, neither of these aubergine alleles silence the Stellate locus. We can conclude that the crystal-Stellate system reveals different RNAi pathways even though much still remains to be done to completely explain the molecular bases of the crystal-Stellate interaction.