Search results for "Sea urchin embryo"
showing 10 items of 70 documents
Perturbation of Developmental Regulatory Gene Expression by a G-Quadruplex DNA Inducer in the Sea Urchin Embryo.
2018
The G-quadruplex (G4) is a four-stranded DNA structure identified in vivo in guanine-rich regions located in the promoter of a number of genes. Intriguing evidence suggested that small molecules acting as G4-targeting ligands could potentially regulate multiple cellular processes via either stabilizing or disruptive effects on G4 motifs. Research in this field aims to prove the direct role of G4 ligands and/or structures on a specific biological process in a complex living organism. In this study, we evaluate in vivo the effects of a nickel(II)-salnaphen-like complex, named Nisaln, a potent G4 binder and stabilizer, during embryogenesis of the sea urchin embryo. We describe developmental de…
Hsp40 Is Involved in Cilia Regeneration in Sea Urchin Embryos
2003
In a previous paper we demonstrated that, in Paracentrotus lividus embryos, deciliation represents a specific kind of stress that induces an increase in the levels of an acidic protein of about 40 kD (p40). Here we report that deciliation also induces an increase in Hsp40 chaperone levels and enhancement of its ectodermal localization. We suggest that Hsp40 might play a chaperoning role in cilia regeneration.
Autophagy as a defense strategy against stress: focus on Paracentrotus lividus sea urchin embryos exposed to cadmium
2015
Autophagy is used by organisms as a defense strategy to face environmental stress. This mechanism has been described as one of the most important intracellular pathways responsible for the degradation and recycling of proteins and organelles. It can act as a cell survival mechanism if the cellular damage is not too extensive or as a cell death mechanism if the damage/stress is irreversible; in the latter case, it can operate as an independent pathway or together with the apoptotic one. In this review, we discuss the autophagic process activated in several aquatic organisms exposed to different types of environmental stressors, focusing on the sea urchin embryo, a suitable system recently in…
Gadolinium perturbs expression of skeletogenic genes, calcium uptake and larval development in phylogenetically distant sea urchin species
2018
Chelates of Gadolinium (Gd), a lanthanide metal, are employed as contrast agents for magnetic resonance imaging and are released into the aquatic environment where they are an emerging contaminant. We studied the effects of environmentally relevant Gd concentrations on the development of two phylogenetically and geographically distant sea urchin species: the Mediterranean Paracentrotus lividus and the Australian Heliocidaris tuberculata. We found a general delay of embryo development at 24 h post-fertilization, and a strong inhibition of skeleton growth at 48 h. Total Gd and Ca content in the larvae showed a time- and concentration-dependent increase in Gd, in parallel with a reduction in C…
Manganese: A New Emerging Contaminant in the Environment
2012
The environment is composed of the atmosphere, earth and water. According to the World Health Organization, more than 100,000 chemicals are released into the global ambient every year as a consequence of their production, use and disposal. The fate of a chemical substance depends on its chemical application and physical-chemical properties, in combination with the characteristics of the environment where it is released. Chemical substances or contaminants discharged into the environment may be “natural” or “manmade”. One of the most misunderstood concepts regarding contamination is the missinterpretation of term “natural”. A “natural” contaminant is one substance that can occur without huma…
From stress proteins to apoptosis and autophagy in sea urchin embryos
2019
Marine invertebrates inhabit a key position as intermediate consumers in the pelagic as well as in the benthonic food chains, making them suitable model systems for ecotoxicological studies. Among benthonic organisms, echinoderms represent a simple, though significant, model system to test how specific stress can simultaneously provoke dangerous effects on growth and vitality of organisms. Sea urchins provide an attractive and exceptional model for investigating environmental pollution. Most studies investigating the effects of Cd stress were conducted on Paracentrotus lividus, one of the most important marine invertebrates used as bioindicator of metal/heavy metal pollution and an importan…
Toxicological Impact of Rare Earth Elements (REEs) on the Reproduction and Development of Aquatic Organisms Using Sea Urchins as Biological Models
2022
The growing presence of lanthanides in the environment has drawn the attention of the scientific community on their safety and toxicity. The sources of lanthanides in the environment include diagnostic medicine, electronic devices, permanent magnets, etc. Their exponential use and the poor management of waste disposal raise serious concerns about the quality and safety of the ecosystems at a global level. This review focused on the impact of lanthanides in marine organisms on reproductive fitness, fertilization and embryonic development, using the sea urchin as a biological model system. Scientific evidence shows that exposure to lanthanides triggers a wide variety of toxic insults, includi…
Autophagy is related to apoptosis in Paracentrotus lividus embryos cadmium exposed
2012
P. lividus embryo offers an excellent opportunity to investigate the adaptive response of cells exposed to different stress. We previously demonstrated that cadmium treatment triggers the accumulation of metal in embryonic cells and the activation of defense system depending on concentration and exposure time, through the synthesis of HSPs and/or the initiation of apoptosis. Analysing autophagy, by neutral red, acridine orange and LC3-detection, we demonstrated that Cd-exposed embryos adopt this process as an additional stratagem to safeguard the developmental program. We observed that embryos treated at subletal Cd concentration activate a massive autophagic response after 18h, which decre…
Specific expression of a TRIM-containing factor in ectoderm cells affects the skeletal morphogenetic program of the sea urchin embryo
2011
In the indirect developing sea urchin embryo, the primary mesenchyme cells (PMCs) acquire most of the positional and temporal information from the overlying ectoderm for skeletal initiation and growth. In this study, we characterize the function of the novel gene strim1, which encodes a tripartite motif-containing (TRIM) protein, that adds to the list of genes constituting the epithelial-mesenchymal signaling network. We report that strim1 is expressed in ectoderm regions adjacent to the bilateral clusters of PMCs and that its misexpression leads to severe skeletal abnormalities. Reciprocally, knock down of strim1 function abrogates PMC positioning and blocks skeletogenesis. Blastomere tran…