Manganese-exposed embryos as blueprints to study signaling pathways involved in development

Developmental defects induced by gadolinium ions in sea urchin embryos of phylogenetically distant species

Gadolinium (Gd) is nowadays an emergent environmental pollutant: it is a metal of the lanthanide series of the elements whose chelates are commonly employed as contrast agents for magnetic resonance imaging and subsequently released into the aquatic environment. Sea urchin embryos are highly sensitive to several kinds of stressors and able to activate different defense strategies. The aim of this study was to analyze the consequences of embryo exposure to sublethal Gd concentrations. We compared the effects of Gd on the development of four phylogenetically distant sea urchin species: two Mediterranean species, Paracentrotus lividus and Arbacia lixula, and two species living in the East coas…

Cellular and molecular bases of biomineralization in sea urchin embryos

Sea urchin embryos construct their skeleton following a precise gene-regulated time- and space-dependent programme, in concert with factors promoting cell adhesion and differentiation. The biomineral is deposited in a privileged extracellular space produced by the fused filopodia processes of the primary mesenchyme cells, the only cells producing a set of necessary matrix proteins. More than ten years ago we showed for the first time that signals from ectoderm cells promoted the expression of one of the major skeleton matrix genes by the primary mesenchyme cells. Since then, many of the crucial steps of this complex activation cascade, from ectoderm cells to embryonic spicules, have been el…

The toxic effect of gadolinium ions on sea urchin embryos: comparison among phylogenetically distant species and focus on mechanisms regulating stress response and skeletogenesis.

Gadolinium (Gd) is a metal of the lanthanide series of the elements whose chelates are commonly employed as contrast agents for magnetic resonance imaging, and subsequently released into the aquatic environment. We investigated the consequences of sea urchin embryo exposure to sublethal Gd concentrations, comparing the effects on the development of four phylogenetically and geographically distant species: two Mediterranean species, Paracentrotus lividus and Arbacia lixula, and two species living in the East coast of Australia, Heliocidaris tuberculata and Centrostephanus rodgersii. Measures of the Gd content inside embryos by ICP-MS showed a time- and dose-dependent increase. In all these s…

Gadolinium-induced stress response causes a time-dependent miss-expression of regulative and structural genes involved in the development of the sea urchin P. lividus

Regulation of Macromolecular Synthesis during Sea Urchin Development

Immediately following fertilization the sea urchin egg enters a period of very rapid cell division that cleaves the egg cell into about one thousand proportionately smaller cells, which form the swimming blastula, i.e. a larval form that is less vulnerable to environmental injuries since it is capable of actively swimming away from them.

Gamma enolase expression as early marker of neuronal differentiation of murine neuroblastoma cells N-115

In this study we determined the levels of gamma enolase mRNA in mouse neuroblastoma cell line N-115 at early period of induction of differentiation by serum withdrawal. The expression of gamma enolase was examined by Northern blot analysis of total RNA extracted from cells induced for different lengths of time. We found a 3-fold increase in the level of gamma enolase mRNA after 24 hours of induction of differentiation and higher levels were detected in cells induced for longer time, reaching a 10-fold increase after four days.

Asimmetric skeleton patterns induced by gadolinium ions in sea urchin embryos: focus on mechanisms regulating skeletogenesis and comparison among phylogenetically distant species

Gadolinium induces autophagy in sea urchin embryos

Biotecnologie e monitoraggio ambientale: sviluppo e applicazione di biomarcatori molecolari.

Effect of environmental stress on sea urchin embryos and larvae: from developmental to molecular biology analyses

Regolazione genica e biomineralizzazione in embrioni di riccio di mare.

Gli echinodermi possiedono un esteso endoscheletro composto da calcite di magnesio, una forma di carbonato di calcio che contiene piccole quantità di carbonato di magnesio e di proteine occluse nella matrice [1]. Nell’ambito del progetto europeo del 7FP Biomintec 2008-2012 (http://www.biomintec.de/), focalizzato sui meccanismi molecolari che stanno alla base dei processi di biomineralizzazione e volto alla futura applicazione di nuovi biomateriali, abbiamo studiato gli effetti della deprivazione di magnesio sullo sviluppo dell’embrione di riccio di mare Arbacia lixula. Gli embrioni sono stati analizzati morfologicamente, valutando l’impatto sullo sviluppo a vari stadi (3, 6, 24, 48 e 72 ore…

La Sicilia nell’Italia dialettale di Giulio Bertoni. I tratti fonetici

In 1916, Bertoni published his essay Italia dialettale in addition to the fundamental studies of Diez, Meyer-Lübke, D’Ovidio and, of course, Ascoli, on which Bertoni builds his geolinguistic reference framework. In that year a series of essays, specifically dedicated to some phonetic aspects of the Sicilian dialect, had already been written by German linguists on one hand and Sicilian folklorists on the other. The only Sicilian linguist at that time was Giacomo De Gregorio whose Saggio di fonetica siciliana (1890) appears among the bibliographic references of Bertoni’s work along with that of Heinrich Schneegans (Laute und Lautentwickelung des sicilianischen Dialects) published in 1888. Thi…

Skeleton growth inhibition in sea urchin embryos Paracentrotus lividus after manganese exposure.

In the sea urchin embryos, skeleton is specified by interactions between PMCs and patterning cues derived from the ectoderm. PMCs use spatial and temporal information to organize the proper animal-vegetal and oral-aboral position and orientation of the two tri-radiate skeletal spicules. Many experiments have demonstrated that exposure to metals, such as lithium, zinc and nickel, can disrupt skeleton patterning information. Here, we have investigated the effects of manganese (Mn) on Paracentrotus lividus embryo development. We found that Mn exposure prevents skeleton growth producing spicule-lacking embryos. Normal skeleton growth was partially rescued after Mn removal from the culture. To d…

Environmentally relevant cadmium concentrations affect development and induce apoptosis of Paracentrotus lividus larvae cultured in vitro. Epub ahead of print.

Sea urchin embryos and larvae represent suitable model systems on where to investigate the effects of heavy metals on development and cell viability. Here, we tested the toxic effects of low (10(-12 )M), medium (10(-9 )M), and high (10(-6 )M) cadmium chloride concentrations, mimicking unpolluted, moderately and highly polluted seawaters, respectively, on Paracentrotus lividus sea urchins offspring. Larvae were continuously treated from fertilization and inspected at time intervals comprised between 10 and 30 days of development. Delays and/or morphological abnormalities were firstly evident in larvae treated for 15 days with high cadmium (10(-6 )M) and for 25 days with medium cadmium (10(-9…

Detection of vitellogenin in a subpopulation of sea urchin coelomocytes.

Sea urchin vitellogenin is a high molecular weight glycoprotein, which is the precursor of the major yolk protein present in the unfertilized egg. Vitellogenin processing into the major yolk protein and its further enzymatic cleavage during sea urchin embryonic development, has been extensively described, and the adhesive properties of the processed molecule have been studied. The function of vitellogenin in the adult, where it has been found in the coelomic fluid of both male and female individuals, is still unknown, although its role on promoting the adhesion of embryonic cells has been shown. In this report we describe the detection of vitellogenin in lysates of whole circulating coelomo…

Cellular, biochemical and molecular effects of cadmium on marine invertebrates: focus on Paracentrotus lividus sea urchin development

Cadmium is a heavy metal that is toxic for living organisms even at low concentrations. The presence in the environment of this metal has grown because of its large employment in some industrial and agricultural activities. Although heavy metals are terrestrially produced, they flow into the sea through effluents and sewage or are directly discharged from industries placed on the seawater front. In addition to its release into costal waters, cadmium fallout, following atmospheric events, contributes to the pollution of marine ecosystems. It should be considered that cadmium concentrations determined in the field vary widely according to different seawater latitudes and depths and can be str…

Considerazioni su alcune dinamiche sociolinguistiche in contesto siculoalbanese

This study investigates diverse sociolinguistic dynamics relating to Sicilian Albanian communities. In light of a survey of the socio-demographic and socio-economic aspects characterising the communities under scrutiny, it has emerged that these communities have a twofold configuration: on the one hand, the community of Piana degli Albanesi presents features of mobility and typically “urban” details, on the other hand, the communities of S. Cristina and Contessa Entellina can be distinguished by an apparent state of isolation and typically “rural” traits. By contrast to what mainstream tendencies may encourage thinking about, the urban socio-economic structured community is sociolinguistica…

Gene expression and stress response in sea urchin embryos with skeleton defects caused by magnesium deprivation.

Echinoderms have an extensive endoskeleton composed of magnesian calcite, a form of calcium carbonate that contains small amounts of magnesium carbonate and occluded matrix proteins [1]. In the frame of the Biomintec European Project focused on the understanding of basic biomineralization mechanisms for the design of novel strategies in nano-biotechnology, we studied the effects of magnesium deprivation on Arbacia lixula sea urchin embryo development. Embryos were morphologically monitored, evaluating developmental abnormalities at different endpoints (3, 6, 24, 48 and 72 hours). In parallel, the spatial transcriptional levels of a skeleton matrix protein (msp130) and the protein synthesis …

Developmental abnormalities induced by Gadolinium causes a time-dependent miss-expression of regulative and structural genes in P. lividus sea urchin embryos

Gadolinium (Gd) is a metal of the lanthanide series of the elements whose chelates are commonly used as contrast agents for magnetic resonance imaging. Its release into the aquatic milieu has posed serious concerns regarding its noxious effects, and therefore Gd is now considered an emerging environmental pollutant. The sea urchin embryo is an excellent model used in both toxicological and developmental research. We analysed the consequences of embryo exposure to sublethal concentrations of Gd on embryo development, focusing on skeletogenesis and developmental symmetry. We observed a strong inhibition of skeleton growth, frequently displayed by an asymmetrical pattern. Continuous exposure t…