%0 Journal Article %J Sustainability %D 2023 %T Local Food Systems under Global Influence: The Case of Food, Health and Environment in Five Socio-Ecosystems %A Rapinski, Michael %A Raymond, Richard %A Davy, Damien %A Herrmann, Thora %A Bedell, Jean-Philippe %A Ka, Abdou %A Odonne, Guillaume %A Chanteloup, Laine %A Pascal Jean Lopez %A Foulquier, Eric %A da Silva, Eduardo Ferreira %A El Deghel, Nathalie %A Boëtsch, Gilles %A Coxam, Véronique %A Joliet, Fabienne %A Guihard-Costa, Anne-Marie %A Tibère, Laurence %A Nazare, Julie-Anne %A Duboz, Priscilla %B Sustainability %V 15 %P 2376 %8 Jan-02-2023 %G eng %U https://www.mdpi.com/2071-1050/15/3/2376 %N 3 %! Sustainability %R 10.3390/su15032376 %0 Journal Article %J Science of The Total Environment %D 2023 %T Temporal pesticide dynamics alter specific eukaryotic taxa in a coastal transition zone %A Hervé, Vincent %A Sabatier, Pierre %A Lambourdière, Josie %A Poulenard, Jérôme %A Pascal Jean Lopez %B Science of The Total Environment %V 866 %P 161205 %8 Jan-03-2023 %G eng %U https://linkinghub.elsevier.com/retrieve/pii/S0048969722083097 %! Science of The Total Environment %R 10.1016/j.scitotenv.2022.161205 %0 Journal Article %J Environmental Science and Pollution Research %D 2022 %T Arsenic and chlordecone contamination and decontamination toxicokinetics in Sargassum sp. %A Devault, Damien A. %A Massat, Félix %A Baylet, Alexandre %A Dolique, Franck %A Pascal Jean Lopez %B Environmental Science and Pollution Research %V 29 %P 6 - 16 %8 Jan-01-2022 %G eng %U https://link.springer.com/10.1007/s11356-020-12127-7 %N 1 %! Environ Sci Pollut Res %R 10.1007/s11356-020-12127-7 %0 Journal Article %J Marine Policy %D 2022 %T Pairing AIS data and underwater topography to assess maritime traffic pressures on cetaceans: Case study in the Guadeloupean waters of the Agoa sanctuary %A Madon, Bénédicte %A Le Guyader, Damien %A Jung, Jean-Luc %A de Montgolfier, Benjamin %A Pascal Jean Lopez %A Foulquier, Eric %A Bouveret, Laurent %A Le Berre, Iwan %B Marine Policy %V 143 %P 105160 %8 Jan-09-2022 %G eng %U https://linkinghub.elsevier.com/retrieve/pii/S0308597X2200207X %! Marine Policy %R 10.1016/j.marpol.2022.105160 %0 Journal Article %J Biodiversity Data Journal %D 2021 %T Kakila database: Towards a FAIR community approved database of cetacean presence in the waters of the Guadeloupe archipelago based on citizen science %A Coché, Lorraine %A Arnaud, Elie %A Bouveret, Laurent %A David, Romain %A Foulquier, Eric %A Gandilhon, Nadège %A Jeannesson, Etienne %A Le Bras, Yvan %A Lerigoleur, Emilie %A Pascal Jean Lopez %A Madon, Bénédicte %A Sananikone, Julien %A Sèbe, Maxime %A Le Berre, Iwan %A Jung, Jean-Luc %A Jung, Jean-Luc %A Coché, Lorraine %A Arnaud, Elie %A Lerigoleur, Emilie %A Pascal Jean Lopez %A Madon, Bénédicte %A Sananikone, Julien %A Sèbe, Maxime %A Le Berre, Iwan %A Jung, Jean-Luc %A Sananikone, Julien %A Sèbe, Maxime %A Le Berre, Iwan %A Jung, Jean-Luc %A Coché, Lorraine %A Arnaud, Elie %A Bouveret, Laurent %A David, Romain %A Foulquier, Eric %A Gandilhon, Nadège %A Jeannesson, Etienne %A Le Bras, Yvan %A Lerigoleur, Emilie %A Pascal Jean Lopez %A Madon, Bénédicte %A Sananikone, Julien %A Sèbe, Maxime %A Le Berre, Iwan %A Jung, Jean-Luc %A Coché, Lorraine %A Arnaud, Elie %A Bouveret, Laurent %A David, Romain %A Foulquier, Eric %A Gandilhon, Nadège %A Jeannesson, Etienne %A Le Bras, Yvan %A Lerigoleur, Emilie %A Pascal Jean Lopez %A Madon, Bénédicte %A Sananikone, Julien %A Sèbe, Maxime %A Le Berre, Iwan %A Jung, Jean-Luc %A Coché, Lorraine %A Arnaud, Elie %A Bouveret, Laurent %A David, Romain %A Foulquier, Eric %A Gandilhon, Nadège %A Jeannesson, Etienne %A Le Bras, Yvan %A Lerigoleur, Emilie %A Pascal Jean Lopez %A Madon, Bénédicte %A Sananikone, Julien %A Sèbe, Maxime %A Le Berre, Iwan %A Jung, Jean-Luc %A Coché, Lorraine %A Arnaud, Elie %A Bouveret, Laurent %A David, Romain %A Foulquier, Eric %A Gandilhon, Nadège %A Jeannesson, Etienne %B Biodiversity Data Journal %V 9 %8 Oct-07-2022 %G eng %U https://bdj.pensoft.net/article/69022/ %! BDJ %R 10.3897/BDJ.9.e69022 %0 Journal Article %J Journal of Applied Phycology %D 2021 %T Sargassum contamination and consequences for downstream uses: a review %A Devault, Damien A. %A Pierre, Ronan %A Marfaing, Hélène %A Dolique, Franck %A Pascal Jean Lopez %B Journal of Applied Phycology %V 33 %P 567 - 602 %8 Jan-02-2021 %G eng %U http://link.springer.com/10.1007/s10811-020-02250-w %N 1 %! J Appl Phycol %R 10.1007/s10811-020-02250-w %0 Journal Article %J Front Microbiol %D 2021 %T Sargassum Differentially Shapes the Microbiota Composition and Diversity at Coastal Tide Sites and Inland Storage Sites on Caribbean Islands %A Hervé, Vincent %A Josie Lambourdière %A René-Trouillefou, Malika %A Devault, Damien Alain %A Pascal Jean Lopez %X

Rafts of drifting pelagic that are circulating across the Atlantic Ocean are complex ecosystems composed of a large number of associated species. Upon massive stranding, they lead to various socio-environmental issues including the inflow of contaminants and human health concerns. In this study, we used metabarcoding approaches to examine the differences in both the eukaryotic- and prokaryotic-associated communities from present in two islands of the Lesser Antilles, namely Guadeloupe and Martinique. We detected significant differences in microbial community structure and composition between landing , the surrounding seawater, and from inland storage sites. In total we identified 22,214 prokaryotic and 17,679 eukaryotic OTUs. Among them, functional prediction analyses revealed a number of prokaryotes that might contribute to organic matter decomposition, nitrogen cycling and gas production, including sulfate-reducing bacteria at coastal landing sites, and methanogenic archaea at inland storage sites. We also found that Metazoan was the most abundant group in samples, with nematode clades that presented exclusive or specific richness and abundance patterns depending on their substrate. Together, these molecular inventories of the micro- and meiofauna communities provide baseline information for further characterization of trophic interactions, algal organic matter decomposition and nutrient transfers at coastal and inland storage sites.

%B Front Microbiol %V 12 %P 701155 %8 2021 %G eng %R 10.3389/fmicb.2021.701155 %0 Journal Article %J Frontiers in Microbiology %D 2021 %T Sargassum Differentially Shapes the Microbiota Composition and Diversity at Coastal Tide Sites and Inland Storage Sites on Caribbean Islands %A Hervé, Vincent %A Lambourdière, Josie %A René-Trouillefou, Malika %A Devault, Damien Alain %A Pascal Jean Lopez %B Frontiers in Microbiology %V 12 %8 May-10-2023 %G eng %U https://www.frontiersin.org/articles/10.3389/fmicb.2021.701155/full %! Front. Microbiol. %R 10.3389/fmicb.2021.701155 %0 Journal Article %J Coral Reefs %D 2021 %T Singular physiological behavior of the scleractinian coral Porites astreoides in the dark phase %A Pascal Claquin %A René-Trouillefou, Malika %A Pascal Jean Lopez %A Japaud, Aurélien %A Yolande Bouchon-Navaro %A Sébastien Cordonnier %A Claude Bouchon %K Caribbean reef corals %K chlororespiration-like %K PAM %K resilience %X Unlike most other corals that have been declining since the 1980s, the population of Porites astreoides, one of the dominant species of coral in Caribbean reefs, appears to be resilient. We investigated the physiological regulation of the electron transport chain of Symbiodiniaceae chloroplasts during the light / dark transition in P. astreoides compared to nine other common scleractinian corals. Protocols were applied to coral samples in seawater tanks and in situ. The maximum quantum yield (Fv/Fm) in the dark and the effective photochemical efficiency (Fq’/Fm’) in the light were measured during light-dark transitions, and alternative electron flow (AEF) mechanisms were evaluated using fluorescence variation in response to serial irradiation pulses (SIP-protocol). The variation in Fv/Fm (ΔYIImax) was calculated after 3 min or 2 h of dark acclimation (ΔYIImax(2h); ΔYIImax(3min)). The three species that belong to the genus Porites (P. astreoides, P. divaricata, P. furcata) showed plastoquinone reduction (PQ) in response to the SIP protocol, unlike all the other species tested. A marked decrease in Fv/Fm (ΔYIImax(2h) = 47.79%) was observed in P. astreoides in the dark whereas the average ΔYIImax(2h) of the other species tested was 0.677%. The decrease in ΔYIImax in P. astreoides was due to a significant increase in Fo (ΔFo(2h) = -108.64% ± SD 21.48) whereas Fm remained relatively stable. The increase in Fo was attributed to reduction of the PQ pool through a chlororespiration-like mechanism known to reduce the production of reactive oxygen species (ROS). This mechanism was triggered immediately after exposure to the dark, while a brief and moderate light exposure reversed it. Given the ecological success of P. astreoides, we suggest that the high antioxidant capability of this species in the dark phase could be one of the factors favoring its survival in the face of various environmental and anthropogenic threats.
  %B Coral Reefs %V doi.org/10.1007/s00338-020-02023-4 %P 139-150 %8 12/2020 %G eng %U https://link.springer.com/article/10.1007/s00338-020-02023-4 %N 40 %0 Journal Article %J Scientific Reports %D 2020 %T Physical properties of epilithic river biofilm as a new lead to perform pollution bioassessments in overseas territories %A Monti, Dominique %A Cédric Hubas %A Lourenço, Xavier %A Begarin, Farid %A Haouisée, Alexandre %A Romana, Laurence %A Lefrançois, Estelle %A Jestin, Alexandra %A Budzinski, Hélène %A Tapie, Nathalie %A Risser, Théo %A Mansot, Jean-Louis %A Philippe Keith %A Gros, Olivier %A Pascal Jean Lopez %A Lauga, Béatrice %X Chlordecone (CLD) levels measured in the rivers of the French West Indies were among the highest values detected worldwide in freshwater ecosystems, and its contamination is recognised as a severe health, environmental, agricultural, economic, and social issue. In these tropical volcanic islands, rivers show strong originalities as simplified food webs, or numerous amphidromous migrating species, making the bioindication of contaminations a difficult issue. The objective of this study was to search for biological responses to CLD pollution in a spatially fixed and long-lasting component of the rivers in the West Indies: the epilithic biofilm. Physical properties were investigated through complementary analyses: friction, viscosity as well as surface adhesion were analyzed and coupled with measures of biofilm carbon content and exopolymeric substance (EPS) production. Our results have pointed out a mesoscale chemical and physical reactivity of the biofilm that can be correlated with CLD contamination. We were able to demonstrate that epilithic biofilm physical properties can effectively be used to infer freshwater environmental quality of French Antilles rivers. The friction coefficient is reactive to contamination and well correlated to carbon content and EPS production. Monitoring biofilm physical properties could offer many advantages to potential users in terms of effectiveness and ease of use, rather than more complex or time-consuming analyses. %B Scientific Reports %V 10 %8 Jan-12-2020 %G eng %U http://www.nature.com/articles/s41598-020-73948-7 %N 1 %! Sci Rep %R 10.1038/s41598-020-73948-7 %0 Journal Article %J Journal of the Royal Society Interface %D 2019 %T Three-dimensional structural evolution of the cuttlefish Sepia officinalis shell from embryo to adult stages %A Le Pabic, Charles %A Derr, Julien %A Luquet, Gilles %A Pascal Jean Lopez %A Laure Bonnaud-Ponticelli %B Journal of the Royal Society Interface %V 16 %P 20190175 %G eng %U https://hal.archives-ouvertes.fr/hal-02318453 %R 10.1098/rsif.2019.0175 %0 Journal Article %J Acta Biomaterialia %D 2018 %T Adhesive gland transcriptomics uncovers a diversity of genes involved in glue formation in marine tube-building polychaetes %A Jean-Philippe Buffet %A Erwan Corre %A Evelyne Duvernois-Berthet %A Jérôme Fournier %A Pascal Jean Lopez %X

Tube-building sabellariid polychaetes are hermatypic organisms capable of forming vast reefs in highly turbulent marine habitats. Sabellariid worms assemble their tube by gluing together siliceous and calcareous clastic particles using a polyelectrolytic biocement. Here, we performed transcriptomic analyses to investigate the genes that are differentially expressed in the parathorax region, which contains the adhesive gland and tissues, from the rest of the body. We found a large number of candidate genes to be involved in the composition and formation of biocement in two species: Sabellaria alveolata and Phragmatopoma caudata. Our results indicate that the glue is likely to be composed by a large diversity of cement-related proteins, including Poly(S), GY-rich, H-repeat and miscellaneous categories. However, sequences divergence and differences in expression profiles between S. alveolata and P. caudata, of cement-related proteins may reflect adaptation to the type of substratum used to build their tube, and/or to their habitat (temperate vs tropical, amplitude of pH, salinity ...). Related to the L-DOPA metabolic pathways and linked with the genes that were differentially expressed in the parathorax region, we found that tyrosinase and peroxidase gene families may have undergone independent expansion in the two Sabellariidae species investigated. Our data also reinforce the importance of protein modifications in cement formation. Altogether these new genomic resources help to identify novel transcripts encoding for cement-related proteins, but also important enzymes putatively involved in the chemistry of the adhesion process, such as kinases, and may correspond to new targets to develop biomimetic approaches.

%B Acta Biomaterialia %G eng %R doi.org/10.1016/j.actbio.2018.03.037 %0 Journal Article %J Estuaries and Coasts %D 2018 %T Annual Phytoplankton Primary Production Estimation in a Temperate Estuary by Coupling PAM and Carbon Incorporation Methods %A Morelle, Jérôme %A Mathilde Schapira %A Francis Orvain %A Riou, Philippe %A Pascal Jean Lopez %A Duplessix, Olivier %A Rabiller, Emilie %A Maheux, Franc %A Simon, Benjamin %A Pascal Claquin %K High frequency . Electron requirement for carbon fixation . Electron transport rate (ETR) . Seine estuary %X

Phytoplankton primary production varies considerably with environmental parameters especially in dynamic ecosystems like estuaries. The aimof this study was to investigate short-term primary production along the salinity gradient of a temperate estuary over the course of 1 year. The combination of carbon incorporation and fluorescence methods enabled primary production estimation at short spatial and temporal scales. The electron requirement for carbon fixation was investigated in relation with physical-chemical parameters to accurately estimate primary production at high frequency. These results combined with the variability of the photic layer allowed the annual estimation of primary production along the estuary. Phytoplankton dynamics was closely related to salinity and turbidity gradients, which strongly influenced cells physiology and photoacclimatation. The number of electrons required to fix 1 mol of carbon (C) was ranged between 1.6 and 25 mol electron mol C−1 with a mean annual value of 8 ± 5 mol electron mol C−1. This optimum value suggests that in nutrient replete conditions like estuaries, alternative electron flows are low, while electrons transfer from photosystem II to carbon fixation is highly efficient. A statistical model was used to improve the estimation of primary production from electron transport rate as a function of significant environmental parameters. Based on this model, daily carbon production in the Seine estuary (France) was estimated by considering light and photic zone variability. A mean annual daily primary production of 0.12 ± 0.18 g C m−2 day−1 with a maximum of 1.18 g C m−2 day−1 in summer was estimated which lead to an annual mean of 64.75 g C m−2 year−1. This approach should be applied more frequently in dynamic ecosystems such as estuaries or coastal waters to accurately estimate primary production in those valuable ecosystems.

%B Estuaries and Coasts %8 02/2018 %G eng %0 Journal Article %J ISME J. %D 2018 %T Aquatic urban ecology at the scale of a capital: community structure and interactions in street gutters. %A Hervé, Vincent %A Leroy, Boris %A Da Silva Pires, Albert %A Pascal Jean Lopez %X

In most cities, streets are designed for collecting and transporting dirt, litter, debris, storm water and other wastes as a municipal sanitation system. Microbial mats can develop on street surfaces and form microbial communities that have never been described. Here, we performed the first molecular inventory of the street gutter-associated eukaryotes across the entire French capital of Paris and the non-potable waters sources. We found that the 5782 OTUs (operational taxonomic units) present in the street gutters which are dominated by diatoms (photoautotrophs), fungi (heterotrophs), Alveolata and Rhizaria, includes parasites, consumers of phototrophs and epibionts that may regulate the dynamics of gutter mat microbial communities. Network analyses demonstrated that street microbiome present many species restricted to gutters, and an overlapping composition between the water sources used for street cleaning (for example, intra-urban aquatic networks and the associated rivers) and the gutters. We propose that street gutters, which can cover a significant surface area of cities worldwide, potentially have important ecological roles in the remediation of pollutants or downstream wastewater treatments, might also be a niche for growth and dissemination of putative parasite and pathogens.The ISME Journal advance online publication, 13 October 2017; doi:10.1038/ismej.2017.166.

%B ISME J. %V 12 %P 253–266 %8 09/2017 %G eng %U https://www.nature.com/articles/ismej2017166 %N 1 %R 10.1038/ismej.2017.166 %0 Journal Article %J Frontiers in marine Science %D 2018 %T Optical Properties of Nanostructured Silica Structures From Marine Organisms %A Mcheik, A %A Cassaignon, S %A Livage, J %A Gibaud, A %A Berthier, S %A Pascal Jean Lopez %K biosilica %K Diatoms %K light-silica interaction %K photonics materials %K sponges %X

Light is important for the growth, behavior, and development of both phototrophic and autotrophic organisms. A large diversity of organisms used silica-based materials as internal and external structures. Nano-scaled well-organized silica biomaterials are characterized by a low refractive index and an extremely low absorption coefficient in the visible range, which make them interesting for optical studies. Recent studies on silica materials from glass sponges and diatoms, have pointed out very interesting optical properties, such as light waveguiding, diffraction, focusing, and photoluminescence. Light guiding and focusing have been shown to be coupled properties found in spicule of glass sponge or shells of diatoms. Moreover, most of these interesting studies have used purified biomaterials and the properties have addressed in non-aquatic environments, first in order to enhance the index contrast in the structure and second to enhance the spectral distribution. Although there is many evidences that silica biomaterials can present interesting optical properties that might be used for industrial purposes, it is important to emphases that the results were obtained from a few numbers of species. Due to the key roles of light for a large number of marine organisms, the development of experiments with living organisms along with field studies are require to better improve our understanding of the physiological and structural roles played by silica structures.

%B Frontiers in marine Science %8 04:2018 %G eng %! Optical Properties of Marine Biosilica %0 Journal Article %J Cybium %D 2018 %T Selectivity on epilithic diatom consumption for two tropical sympatric gobies: Sicydium punctatum (Perugia 1986) and Sicydium plumieri (Bloch 1786) %A Monti, Dominique %A Lefrançois, F %A Clara Lord %A Jean-Michel Mortillaro %A Pascal Jean Lopez %A Philippe Keith %K Biofilm %K Bioindication %K Caribbean Islands %K Gobiidae %K Tropical rivers %X

 

 Rivers of the Caribbean islands harbour a freshwater fauna mainly constituted of migrant diadromous species. In these hyperturbulent ecosystems, the primary producers are mostly represented by a thin epilithic biofilm, mainly composed of diatoms. Comparison of the diatoms available from the environment with the ones consumed and located in the digestive tracts of two gobiid fish, Sicydium punctatum Perugia, 1896 and Sicydium plumieri (Bloch, 1786) were made at twelve sampling locations, located upstream or downstream of six rivers, in Guadeloupe. One hundred and ninety-one epilithic diatom species were identified. A statistical approach was used to determine diatoms that best characterize the two species digestive tracts content (i.e. “diagnostic species”) and to evaluate the statistical relationship between species abundances and groups of sites or conditions. Eight taxa belonging to five families were considered as significant diagnostic species of digestive tracts from fish collected upstream (Achnanthidium subhudsonis, Achnanthes rupestoides, Diadesmis contenta, Diadesmis sp., Eolimna sp., Navicula (dicta) seminulum, Navicula difficillima and Nupela sp.), and five taxa belonging to three families were considered as significant diagnostic species for fish collected downstream (Gomphonema parvulum, Navicula arvensis, Navicula cruxmeridionalis, Nitzschia frustulum and Navicula incarum). Results indicate selective consumption of epilithic diatoms by the two major fish observed in the mid and upper stream of Caribbean rivers

%B Cybium %V 42 %P 365-373 %G eng %N 4 %0 Journal Article %J Front. Physiol. %D 2017 %T Eye Development in Sepia officinalis Embryo: What the Uncommon Gene Expression Profiles Tell Us about Eye Evolution %A Imarazen, Boudjema %A Aude Andouche %A Yann Bassaglia %A Pascal Jean Lopez %A Laure Bonnaud-Ponticelli %K dac %K eya %K eye development %K rhodopsin %K Sepia officinalis %K six %X

In metazoans, there is a remarkable diversity of photosensitive structures; their shapes, physiology, optical properties, and development are different. To approach the evolution of photosensitive structures and visual function, cephalopods are particularly interesting organisms due to their most highly centralized nervous system and their camerular eyes which constitute a convergence with those of vertebrates. The eye morphogenesis in numerous metazoans is controlled mainly by a conserved Retinal Determination Gene Network (RDGN) including pax, six, eya, and dac playing also key developmental roles in non-retinal structures and tissues of vertebrates and Drosophila. Here we have identified and explored the role of Sof-dac, Sof-six1/2, Sof-eya in eye morphogenesis, and nervous structures controlling the visual function in Sepia officinalis. We compare that with the already shown expressions in eye development of Sof-otx and Sof-pax genes. Rhodopsin is the pigment responsible for light sensitivity in metazoan, which correlate to correlate visual function and eye development. We studied Sof-rhodopsin expression during retina differentiation. By in situ hybridization, we show that (1) all of the RDGN genes, including Sof-pax6, are expressed in the eye area during the early developmental stages but they are not expressed in the retina, unlike Sof-otx, which could have a role in retina differentiation; (2) Sof-rhodopsin is expressed in the retina just before vision gets functional, from stage 23 to hatching. Our results evidence a role of Sof-six1/2, Sof-eya, and Sof-dac in eye development. However, the gene network involved in the retinal photoreceptor differentiation remains to be determined. Moreover, for the first time, Sof-rhodopsin expression is shown in the embryonic retina of cuttlefish suggesting the evolutionary conservation of the role of rhodopsin in visual phototransduction within metazoans. These findings are correlated with the physiological and behavioral observations suggesting that S. officinalis is able to react to light stimuli from stage 25 of organogenesis on, as soon as the first retinal pigments appear.

%B Front. Physiol. %8 08/2017 %G eng %R 10.3389/fphys.2017.00613 %0 Journal Article %J J Proteomics %D 2017 %T First proteomic analyses of the dorsal and ventral parts of the Sepia officinalis cuttlebone. %A Le Pabic, Charles %A Marie, Arul %A Marie, Benjamin %A Percot, Aline %A Laure Bonnaud-Ponticelli %A Pascal Jean Lopez %A Gilles Luquet %X

Protein compounds constituting mollusk shells are known for their major roles in the biomineralization processes. These last years, a great diversity of shell proteins have been described in bivalves and gastropods allowing a better understanding of the calcification control by organic compounds and given promising applications in biotechnology. Here, we analyzed for the first time the organic matrix of the aragonitic Sepia officinalis shell, with an emphasis on protein composition of two different structures: the dorsal shield and the chambered part. Our results highlight an organic matrix mainly composed of polysaccharide, glycoprotein and protein compounds as previously described in other mollusk shells, with quantitative and qualitative differences between the dorsal shield and the chamber part. Proteomic analysis resulted in identification of only a few protein compounds underlining the lack of reference databases for Sepiidae. However, most of them contain domains previously characterized in matrix proteins of aragonitic shell-builder mollusks, suggesting ancient and conserved mechanisms of the aragonite biomineralization processes within mollusks.

BIOLOGICAL SIGNIFICANCE: The cuttlefish's inner shell, better known under the name "cuttlebone", is a complex mineral structure unique in mollusks and involved in tissue support and buoyancy regulation. Although it combines useful properties as high compressive strength, high porosity and high permeability, knowledge about organic compounds involved in its building remains limited. Moreover, several cuttlebone organic matrix studies reported data very different from each other or from other mollusk shells. Thus, this study provides 1) an overview of the organization of the main mineral structures found in the S. officinalis shell, 2) a reliable baseline about its organic composition, and 3) a first descriptive proteomic approach of organic matrices found in the two main parts of this shell. These data will contribute to the general knowledge about mollusk biomineralization as well as in the identification of protein compounds involved in the Sepiidae shell calcification.

%B J Proteomics %V 150 %P 63-73 %8 2016 Aug 26 %G eng %R 10.1016/j.jprot.2016.08.015 %0 Journal Article %J Environmental Microbiology %D 2017 %T Physiological adjustments and transcriptome reprogramming are involved in the acclimation to salinity gradients in diatoms %A Adrien Bussard %A Corre, Erwan %A Cédric Hubas %A Duvernois‐Berthet, Evelyne %A Gildas Le Corguille %A Jourdren, Laurent %A Coulpier, Fanny %A Pascal Claquin %A Pascal Jean Lopez %X

Salinity regimes in estuaries and coastal areas vary with river discharge patterns, seawater evaporation, the morphology of the coastal waterways, and the dynamics of marine water mixing. Therefore, microalgae have to respond to salinity variations at time scales ranging from daily to annual cycles. Microalgae may also have to adapt to physical alterations that induce the loss of connectivity between habitats and the enclosure of bodies of water. Here, we integrated physiological assays and measurements of morphological plasticity with a functional genomics approach to examine the regulatory changes that occur during the acclimation to salinity in the estuarine diatom Thalassiosira weissflogii. We found that cells exposed to different salinity regimes for a short or long period presented adjustments in their carbon fractions, silicon pools, pigment concentrations and/or photosynthetic parameters. Salinity-induced alterations in frustule symmetry were observed only in the long-term cultures. Whole transcriptome analyses revealed a down-regulation of nuclear and plastid encoded genes during the long-term response and identified only a few regulated genes that were in common between the short- and long-term responses. We propose that in diatoms, one strategy for acclimating to salinity gradients and maintaining optimal cellular fitness could be a reduction in the cost of transcription. This article is protected by copyright. All rights reserved.

%B Environmental Microbiology %V 19 %P 909-925 %8 5 %G eng %U http://dx.doi.org/10.1111/1462-2920.13398 %N 3 %R 10.1111/1462-2920.13398 %0 Journal Article %J Journal of Marine Science and Technology %D 2014 %T Evolution of Vacuolar Pyrophosphatases and Vacuolar H+-Atpases in Diatoms %A Adrien Bussard %A Pascal Jean Lopez %K Algae %K endoplasmic reticulum %K H^+-PPases %K V-ATPases %K vacuole %X

To cope with changing environments and maintain optimal metabolic conditions, the control of the intracellular proton gradients has to be tightly regulated. Among the important proton pumps, vacuolar H^+-ATPases (V-ATPases) and H^+-translocating pyrophosphatases (H^+-PPases) were found to be involved in a number of physiological processes, and shown to be regulated at the expression level and to exhibit specific sub-cellular localizations. Studies of the role of these transporters are relatively scarce in algae and nearly absent in diatoms. Phylogenetic analyses disclose that diatoms, with both K^+-dependent and K^+-independent membrane integral pyrophosphatases, including proteins with high homology with a novel class of Na^+,H^+-PPases. Analyses of Phaeodactylum tricornutum EST libraries show that the gene putatively encoding a Na^+,H^+-PPase is over-expressed in urea adapted condition. Genome-wide investigations of the reservoir of V-ATPases encoding subunits demonstrate that diatoms display an expended number of genes encoding for the proteolipid subunits c of the V0 subcomplex. Preliminary localization studies show that one of V0-c subunits is associated to the endoplasmic reticulum membrane in P. tricornutum. Altogether our data highlight that the combination of comparative and functional genomic approaches reach promises to provide new information to the roles of membrane proton pumps in diatoms.

%B Journal of Marine Science and Technology %V 22 %P 50-59 %8 Feb %G eng %R 10.6119/JMST-013-0829-1