Publications by authors named "Renata Boucher-Rodoni"

5 Publications

  • Page 1 of 1

Occurrence of a specific dual symbiosis in the excretory organ of geographically distant Nautiloids populations.

Environ Microbiol Rep 2012 Oct 18;4(5):504-11. Epub 2012 May 18.

Coral Reef Ecosystem Laboratory, School of Biological Sciences, The University of Queensland, Gehrmann building (#60), Level 7, St Lucia, Queensland 4072, Australia UMR 7208 'Biologie des ORganismes et Ecosytèmes Aquatiques' MNHN-CNRS-IRD-UPMC - Case postale 53, 75231 Paris cedex 05, France Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.

Nautilus is one of the most intriguing of all sea creatures, sharing morphological similarities with the extinct forms of coiled cephalopods that evolved since the Cambrian (542-488 mya). Further, bacterial symbioses found in their excretory organ are of particular interest as they provide a great opportunity to investigate the influence of host-microbe interactions upon the origin and evolution of an innovative nitrogen excretory system. To establish the potential of Nautilus excretory organ as a new symbiotic system, it is, however, necessary to assess the specificity of this symbiosis and whether it is consistent within the different species of present-day Nautiloids. By addressing the phylogeny and distribution of bacterial symbionts in three Nautilus populations separated by more than 6000 km (N. pompilius from Philippines and Vanuatu, and N. macromphalus from New Caledonia), this study confirms the specificity of this dual symbiosis involving the presence of betaproteobacteria and spirochaete symbionts on a very wide geographical area. Overall, this work sheds further light on Nautiloids excretory organ as an innovative system of interaction between bacteria and cephalopods.
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http://dx.doi.org/10.1111/j.1758-2229.2012.00352.xDOI Listing
October 2012

Comparative bioaccumulation of trace elements between Nautilus pompilius and Nautilus macromphalus (Cephalopoda: Nautiloidea) from Vanuatu and New Caledonia.

Ecotoxicol Environ Saf 2009 Feb 16;72(2):365-71. Epub 2008 Jun 16.

UMR 5178 Biologie des Organismes Marins et Ecosystèmes, DMPA, Muséum National d'Histoire Naturelle, 55 rue Buffon, 75005 Paris, France.

The concentrations of 16 trace elements were investigated and compared for the first time in the digestive and excreting tissues of two Nautilus species (Cephalopoda: Nautiloidea) from two geologically contrasted areas: (1) N. macromphalus from New Caledonia, a region characterized by its richness in nickel ores and its lack of tectonic activities and (2) N. pompilius from the Vanuatu archipelago showing high volcanic and tectonic activities. In both Nautilus species, results clearly highlighted that the digestive gland played a key role in the bioaccumulation and storage of Ag, Cd, Ce, Co, Cu, Fe, La, Nd, V, and Zn whereas As, Cr, Mn, Ni, Pb, and Se were accumulated in a greater extent in the excreting tissues (i.e. pericardial and renal appendages). Despite contrasting environments, no significant difference (p<0.05) was found between the two Nautilus species in the concentrations of most of the essential and non-essential elements, including Ni and associated metals in Ni ores (i.e. Co and Mn). As nautilus lives on the outer shelf of barrier reefs, these results strongly support the hypothesis that the New Caledonian lagoon traps the major amount of the trace elements derived from natural erosion and the intense mining activities conducted on land. In contrast, the concentrations of the rare earth elements (Ce, La, and Nd) were significantly higher in N. pompilius than in N. macromphalus, probably as a result of the local enrichment of Vanuatu waters by specific environmental processes, such as volcanism or upwelling.
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http://dx.doi.org/10.1016/j.ecoenv.2008.04.019DOI Listing
February 2009

Enigmatic dual symbiosis in the excretory organ of Nautilus macromphalus (Cephalopoda: Nautiloidea).

Proc Biol Sci 2007 May;274(1614):1143-52

UMR 5178 Biologie des Organismes Marins et Ecosystèmes, Département Peuplements et Milieux Aquatiques, Muséum National d'Histoire Naturelle, 55 rue Buffon, 75005 Paris, France.

Symbiosis is an important driving force in metazoan evolution and the study of ancient lineages can provide an insight into the influence of symbiotic associations on morphological and physiological adaptations. In the 'living fossil' Nautilus, bacterial associations are found in the highly specialized pericardial appendage. This organ is responsible for most of the excretory processes (ultrafiltration, reabsorption and secretion) and secretes an acidic ammonia-rich excretory fluid. In this study, we show that Nautilus macromphalus pericardial appendages harbour a high density of a beta-proteobacterium and a coccoid spirochaete using transmission electron microscopy, comparative 16S rRNA sequence analysis and fluorescence in situ hybridization (FISH). These two bacterial phylotypes are phylogenetically distant from any known bacteria, with ammonia-oxidizing bacteria as the closest relatives of the beta-proteobacterium (above or equal to 87.5% sequence similarity) and marine Spirochaeta species as the closest relatives of the spirochaete (above or equal to 89.8% sequence similarity), and appear to be specific to Nautilus. FISH analyses showed that the symbionts occur in the baso-medial region of the pericardial villi where ultrafiltration and reabsorption processes take place, suggesting a symbiotic contribution to the excretory metabolism.
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http://dx.doi.org/10.1098/rspb.2006.0353DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2189564PMC
May 2007

Unexpected variation of Hox genes' homeodomains in cephalopods.

Mol Phylogenet Evol 2006 Sep 26;40(3):872-9. Epub 2006 Apr 26.

Développement et Evolution, UMR 7622, CNRS et Université P et M Curie, Paris 6, Case 24, 9 quai St Bernard, 75252 Paris Cedex 05, France.

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http://dx.doi.org/10.1016/j.ympev.2006.04.004DOI Listing
September 2006

A molecular and karyological approach to the taxonomy of Nautilus.

C R Biol 2004 Feb;327(2):133-8

Département Milieux et Peuplements aquatiques, UMR 5178 (BOME), Muséum national d'histoire naturelle, Institut Jacques-Monod-CNRS, universités Paris-6 & -7, 2, Paris, France.

Nautiloids, the externally shelled cephalopods of Cambrian origin, are the most ancient lineage among extant cephalopods. Their ancestral characters are explored based on morphological and molecular data (18S rDNA sequence) to investigate the evolution of present cephalopod lineages. Among molluscs, nautilus 18S rDNA gene is the longest reported so far, due to large nucleotidic insertions. By comparison with other 18S sequences, the complete gene of N. macromphalus helps to clarify the taxonomic status of the three universally recognised Nautilus species. The range of interspecific molecular differences supports separation of the present species into two surviving ectocochleate genera, Nautilus and Allonautilus. Nautiloid 18S is considered as corresponding to the ancestral form of 18S as is the number of chromosomes in Nautilus (52), the lowest among cephalopods. Comparison of karyological characteristics amongst cephalopods in a phylogenetic context suggests a possible correlation between duplication events and lineage divergence.
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http://dx.doi.org/10.1016/j.crvi.2003.12.004DOI Listing
February 2004