scholarly journals The reproductive response of the sea urchins Paracentrotus lividus (G.) and Psammechinus miliaris (L.) to a hyperproteinated macrophytic diet

2006 ◽  
Vol 339 (1) ◽  
pp. 43-54 ◽  
Author(s):  
Anne-Gaëlle Jacquin ◽  
Anne Donval ◽  
Jacques Guillou ◽  
Sandra Leyzour ◽  
Eric Deslandes ◽  
...  
Keyword(s):  
Sea Urchins ◽  
Paracentrotus Lividus ◽  
Psammechinus Miliaris ◽  
Reproductive Response

scholarly journals Echinochrome A Release by Red Spherule Cells Is an Iron-Withholding Strategy of Sea Urchin Innate Immunity

2017 ◽  
Vol 10 (2) ◽  
pp. 119-130 ◽  
Author(s):  
Christopher J. Coates ◽  
Claire McCulloch ◽  
Joshua Betts ◽  
Tim Whalley
Keyword(s):  
Ex Vivo ◽  
Sea Urchins ◽  
Antimicrobial Properties ◽  
Paracentrotus Lividus ◽  
Iron Chelator ◽  
Coelomic Fluid ◽  
Echinochrome A ◽  
Psammechinus Miliaris ◽  
Spherule Cell ◽  
Cellular Immune

Cellular immune defences in sea urchins are shared amongst the coelomocytes - a heterogeneous population of cells residing in the coelomic fluid (blood equivalent) and tissues. The most iconic coelomocyte morphotype is the red spherule cell (or amebocyte), so named due to the abundance of cytoplasmic vesicles containing the naphthoquinone pigment echinochrome A. Despite their identification over a century ago, and evidence of antiseptic properties, little progress has been made in characterising the immunocompetence of these cells. Upon exposure of red spherule cells from sea urchins, i.e., Paracentrotus lividus and Psammechinus miliaris, to microbial ligands, intact microbes, and damage signals, we observed cellular degranulation and increased detection of cell-free echinochrome in the coelomic fluid ex vivo. Treatment of the cells with ionomycin, a calcium-specific ionophore, confirmed that an increase in intracellular levels of Ca2+ is a trigger of echinochrome release. Incubating Gram-positive/negative bacteria as well as yeast with lysates of red spherule cells led to significant reductions in colony-forming units. Such antimicrobial properties were counteracted by the addition of ferric iron (Fe3+), suggesting that echinochrome acts as a primitive iron chelator in echinoid biological defences.

scholarly journals Sub-Chronic Effects of Slight PAH- and PCB-Contaminated Mesocosms in Paracentrotus lividus Lmk: A Multi-Endpoint Approach and De Novo Transcriptomic

2021 ◽  
Vol 22 (13) ◽  
pp. 6674
Author(s):  
Luisa Albarano ◽  
Valerio Zupo ◽  
Davide Caramiello ◽  
Maria Toscanesi ◽  
Marco Trifuoggi ◽  
...  
Keyword(s):  
De Novo ◽  
Sea Urchins ◽  
Transcriptome Assembly ◽  
Paracentrotus Lividus ◽  
Marine Biota ◽  
De Novo Transcriptome Assembly ◽  
De Novo Transcriptome ◽  
Limit Values ◽  
The Impact ◽  
Endpoint Approach

Sediment pollution is a major issue in coastal areas, potentially endangering human health and the marine environments. We investigated the short-term sublethal effects of sediments contaminated with polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) on the sea urchin Paracentrotus lividus for two months. Spiking occurred at concentrations below threshold limit values permitted by the law (TLVPAHs = 900 µg/L, TLVPCBs = 8 µg/L, Legislative Italian Decree 173/2016). A multi-endpoint approach was adopted, considering both adults (mortality, bioaccumulation and gonadal index) and embryos (embryotoxicity, genotoxicity and de novo transcriptome assembly). The slight concentrations of PAHs and PCBs added to the mesocosms were observed to readily compartmentalize in adults, resulting below the detection limits just one week after their addition. Reconstructed sediment and seawater, as negative controls, did not affect sea urchins. PAH- and PCB-spiked mesocosms were observed to impair P. lividus at various endpoints, including bioaccumulation and embryo development (mainly PAHs) and genotoxicity (PAHs and PCBs). In particular, genotoxicity tests revealed that PAHs and PCBs affected the development of P. lividus embryos deriving from exposed adults. Negative effects were also detected by generating a de novo transcriptome assembly and its annotation, as well as by real-time qPCR performed to identify genes differentially expressed in adults exposed to the two contaminants. The effects on sea urchins (both adults and embryos) at background concentrations of PAHs and PCBs below TLV suggest a need for further investigations on the impact of slight concentrations of such contaminants on marine biota.

scholarly journals Contrasting recruitment seasonality of sea urchin species in Gran Canaria, Canary Islands (eastern Atlantic)

2014 ◽  
Vol 15 (3) ◽  
pp. 475 ◽  
Author(s):  
S. GARCIA-SANZ ◽  
P. G. NAVARRO ◽  
F. TUYA
Keyword(s):  
Community Structure ◽  
Seasonal Variation ◽  
Sea Urchin ◽  
Sea Urchins ◽  
Late Summer ◽  
Paracentrotus Lividus ◽  
Abundant Species ◽  
Late Winter ◽  
Gran Canaria ◽  
Arbacia Lixula

Despite sea-urchins can play an important role affecting the community structure of subtidal bottoms, factors controlling the dynamics of sea-urchin populations are still poorly understood. We assessed the seasonal variation in recruitment of three sea-urchin species (Diadema africanum, Paracentrotus lividus and Arbacia lixula) at Gran Canaria Island (eastern Atlantic) via monthly deployment of artificial collectors throughout an entire annual cycle on each of four adjacent habitat patches (seagrasses, sandy patches, ‘urchin-grazed’ barrens and macroalgal-dominated beds) within a shallow coastal landscape. Paracentrotus lividus and A. lixula had exclusively one main recruitment peak in late winter-spring. Diadema africanum recruitment was also seasonal, but recruits appeared in late summer-autumn, particularly on ‘urchin-grazed’ barrens with large abundances of adult conspecifics. In conclusion, this study has demonstrated non-overlapping seasonal recruitment patterns of the less abundant species (P. lividus and A. lixula) with the most conspicuous species (D. africanum) in the study area.

scholarly journals Diverse Transformers (Trf) Protein Family in the Sea Urchin Paracentrotus lividus Act through Collaboration between Cellular and Humoral Immune Effector Arms

2021 ◽  
Author(s):  
Iryna Yakovenko ◽  
Asaf Donnyo ◽  
Or Ioscovich ◽  
Benyamin Rosental ◽  
Matan Oren
Keyword(s):  
Sea Urchin ◽  
Sea Urchins ◽  
Paracentrotus Lividus ◽  
Protein Family ◽  
Immune Gene ◽  
Immune Effector ◽  
E Coli ◽  
Purple Sea Urchin ◽  
Humoral Immune ◽  
Extended Families

Sea urchins are long-living invertebrates with a complex immune system which includes extended families of immune receptors. A central immune gene family in the sea urchins encodes for the Transformer (Trf) proteins. The Trf family was so far studied mainly in the purple sea urchin Strongylocentrotus purpuratus. In this study, we explored this protein family in the Mediterranean Sea urchin Paracentrotus lividus. The PlTrf genes and predicted proteins were found to be highly diverse and showed a typical Trf size range and structure. We found that P. lividus coelomocytes and hemolymph contain different PlTrf protein repertoires with a shared subset which specifically bind E. coli bacteria. Using FACS, we identified five different P. lividus coelomocyte sub-populations with cell surface Trf protein expression. The relative abundance of the Trf-positive cells sharply increased following immune challenge with E. coli bacteria, but not following challenge with LPS or sea urchin pathogen V. penaeicida. Finally, we demonstrated that the phagocytosis of E. coli bacteria by P. lividus phagocytes is mediated through the hemolymph and is inhibited by blocking Trf activity with anti-Trf antibodies. Together, our results suggest collaboration between cellular and humoral Trf-mediated effector arms in the P. lividus specific immune response to pathogens.

scholarly journals Complex Mixture-Associated Hormesis and Toxicity: The Case of Leather Tanning Industry

Dose-Response ◽  
2008 ◽  
Vol 6 (4) ◽  
pp. dose-response.0 ◽  
Author(s):  
Giovanni Pagano ◽  
Giuseppe Castello ◽  
Marialuisa Gallo ◽  
Ilaria Borriello ◽  
Marco Guida
Keyword(s):  
Growth Inhibition ◽  
Sea Urchin ◽  
Sea Urchins ◽  
Complex Mixture ◽  
Algal Growth ◽  
Paracentrotus Lividus ◽  
Selenastrum Capricornutum ◽  
Tannery Effluent ◽  
Developmental Defects ◽  
Algal Growth Inhibition

A series of studies investigated the toxicities of tannery-derived complex mixtures, i.e. vegetable tannin (VT) from Acacia sp. or phenol-based synthetic tannin (ST), and wastewater from tannin-based vs. chromium-based tanneries. Toxicity was evaluated by multiple bioassays including developmental defects and loss of fertilization rate in sea urchin embryos and sperm ( Paracentrotus lividus and Sphaerechinus granularis), and algal growth inhibition ( Dunaliella tertiolecta and Selenastrum capricornutum). Both VT and ST water extracts resulted in hormetic effects at concentrations ranging 0.1 to 0.3%, and toxicity at levels ≥1%, both in sea urchin embryo and sperm, and in algal growth bioassays. When comparing tannin-based tannery wastewater (TTW) vs. chromium-based tannery effluent (CTE), a hormesis to toxicity trend was observed for TTW both in terms of developmental and fertilization toxicity in sea urchins, and in algal growth inhibition, with hormetic effects at 0.1 to 0.2% TTW, and toxicity at TTW levels ≥1%. Unlike TTW, CTE showed a monotonic toxicity increase from the lowest tested level (0.1%) and CTE toxicity at higher levels was significantly more severe than TTW-induced toxicity. The results support the view that leather production utilizing tannins might be regarded as a more environmentally friendly procedure than chromium-based tanning process.

The Fertilization Reaction in the Sea-Urchin

1952 ◽  
Vol 29 (3) ◽  
pp. 469-483
Author(s):  
LORD ROTHSCHILD ◽  
M. M. SWANN
Keyword(s):  
Sea Urchin ◽  
Sea Urchins ◽  
Standard Errors ◽  
Conduction Time ◽  
Normal Sperm ◽  
Psammechinus Miliaris ◽  
Sperm Suspension ◽  
Small Incidence ◽  
High Concentrations ◽  
First Time

1. The reactions of sea-urchin eggs (Psammechinus miliaris) to high concentrations of homologous spermatozoa have been investigated by a new method. 2. The method was to inseminate eggs with high concentrations of spermatozoa (108/ml.), which ensured that all eggs were fertilized for the first time at the beginning of the experiment; and then functionally to separate the eggs and spermatozoa at known times after the original insemination. 3. The proportion of polyspermic eggs in the suspension rises from zero at t=0 to a constant value at a time T, which is the conduction time of the block to polyspermy. In fourteen experiments on eggs from different sea-urchins, the estimated values of T were 17, 69, 72, 74, 94, 85, 26, 60, 31, 91, 85, 34, 75 and 67 sec. (arithmetic mean 63 sec.). The standard errors of the estimates of T, which are tabulated in the text, ranged from 5 to 15 sec. 4. These results confirm previous experiments which strongly suggested that the conduction time of the block to polyspermy was of the order of seconds; these earlier experiments were incompatible with a block to polyspermy lasting a fraction of a second. 5. At the same time experiments in this paper made it possible to estimate the fertilization parameter or sperm-egg interaction rate α, during the conduction of the block to polyspermy, and to compare it with the pre-fertilization α. In a given sperm suspension, α is a measure of the receptivity of the egg surface to spermatozoa. During the conduction of the block to polyspermy α was found to be markedly lower (1/20) than in unfertilized eggs. 6. This suggests that at fertilization there is a fast but incomplete block to polyspermy, whose conduction time may be 1 sec. or less. This is followed by the slower block which finally makes the egg impermeable to spermatozoa. This also confirms previous observations on the small incidence of polyspermy at normal sperm densities, which is not consistent with the concept of a slow block to polyspermy.

Unexpected conversion of echinochrome to brominated spinochrome D. Synthesis of 2-amino-3,6,7-trihydroxynaphthazarin produced by the sea urchins Strongylocentrotus nudus and Psammechinus miliaris

2016 ◽  
Vol 57 (7) ◽  
pp. 736-738 ◽  
Author(s):  
Galina I. Melman ◽  
Ksenia L. Borisova ◽  
Nataly D. Pokhilo ◽  
Vyacheslav V. Makhankov ◽  
Victor Ph. Anufriev
Keyword(s):  
Sea Urchins ◽  
Psammechinus Miliaris ◽  
Strongylocentrotus Nudus
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