The long-term adaptation of multicellular model organisms to non-terrestrial and space environments

The main point in this presentation is the following: It is of crucial importance that the Space Agencies define and support the long-term directions for Space Biology Research. The development and upgrading of Facilities and Carriers should be coordinated with the preparatory activities of scientific groups interested in tackling major questions using the future opportunities in the Space Exploration Programs. The current effort in establishing larger Research Networks may lead the way to a successful Space Program in the XXI Century.     

Genetic diversity and genetic structure of black alder (<Emphasis Type="Italic">Alnus glutinosa</Emphasis> [L.] Gaertn) in the Belgium-Luxembourg-France cross-border area

Due to its beneficial effects on river ecosystems, black alder (Alnus glutinosa) is one of the tree species selected for planting on riverbanks in the cross-border area encompassing Wallonia in Belgium, Lorraine in France, and Luxembourg. The preservation of this species, however, is threatened by an invasive pathogen that particularly targets and kills young alder individuals. The objectives of this study were to characterize the genetic diversity and the genetic structure of A. glutinosa at this local level with the aim of assisting the conservation and replanting strategies and to determine if a germplasm collection comprising individuals from the same cross-border area captures the diversity present in the region. Nuclear simple sequence repeat (SSR) and chloroplastic DNA (cpDNA) markers were used to analyze four local wild populations and the germplasm collection which is representative of two river catchments and six legal provenance regions. Three populations distant from the studied area were also included. A panel of 14 nuclear SSR loci revealed high allelic diversity and very low differentiation among wild populations (mean F _ST?=?0.014). The germplasm collection displayed a range of alleles that were representative of the different populations, and no significant differentiation between the germplasm collection and the local wild populations was observed, making this collection, as far as allelic diversity is concerned, suitable for providing trees for riverbank replanting programs. Using SSR markers, various statistical approaches consistently indicated the lack of a significant geographical structure at the level of the river catchments or provenance regions. In contrast, two cpDNA haplotypes were detected and displayed a cross-border geographically structured distribution that could be taken into account in defining new cross-border provenance regions.     

Rapid detection of members of the family Enterobacteriaceae by a monoclonal antibody.

Six monoclonal antibodies directed against enterobacteria were produced and characterized. The specificity of one of these antibodies (CX9/15; immunoglobulin G2a) was studied by indirect immunofluorescence against 259 enterobacterial strains and 125 other gram-negative bacteria. All of the enterobacteria were specifically recognized, the only exception being Erwinia chrysanthemi (one strain tested). Bacteria not belonging to members of the family Enterobacteriaceae were not detected, except for Plesiomonas shigelloides (two strains tested), Aeromonas hydrophila (five strains tested), and Aeromonas sobria (one strain tested). This recognition spectrum strongly suggested that CX9/15 recognized the enterobacterial common antigen. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot (immunoblot) experiments, the six antienterobacteria antibodies presented similar specificities; they all revealed only one band with an apparent molecular weight of about 20,000 from the crude extract of an enterobacterium. The six monoclonal antibodies, and especially CX9/15, can be used to develop new tests for rapid and specific detection of enterobacteria.     

Global Demand for Natural Resources Eliminated More Than 100,000 Bornean Orangutans

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Impaired processing of FLP and NLP peptides in carboxypeptidase E (EGL-21)-deficient Caenorhabditis elegans as analyzed by mass spectrometry

Biologically active peptides are synthesized from inactive pre-proproteins or peptide precursors by the sequential actions of processing enzymes. Proprotein convertases cleave the precursor at pairs of basic amino acids, which are then removed from the carboxyl terminus of the generated fragments by a specific carboxypeptidase. Caenorhabditis elegans strains lacking proprotein convertase EGL-3 display a severely impaired neuropeptide profile (Husson et al. 2006, J. Neurochem.98, 1999-2012). In the present study, we examined the role of the C. elegans carboxypeptidase E orthologue EGL-21 in the processing of peptide precursors. More than 100 carboxy-terminally extended neuropeptides were detected in egl-21 mutant strains. These findings suggest that EGL-21 is a major carboxypeptidase involved in the processing of FMRFamide-like peptide (FLP) precursors and neuropeptide-like protein (NLP) precursors. The impaired peptide profile of egl-3 and egl-21 mutants is reflected in some similar phenotypes. They both share a severe widening of the intestinal lumen, locomotion defects, and retention of embryos. In addition, egl-3 animals have decreased intestinal fat content. Taken together, these results suggest that EGL-3 and EGL-21 are key enzymes for the proper processing of neuropeptides that control egg-laying, locomotion, fat storage and the nutritional status.     

Altered neuropeptide profile of Caenorhabditis elegans lacking the chaperone protein 7B2 as analyzed by mass spectrometry

Cellular synthesis of naturally occurring, bioactive peptides requires the proprotein convertase PC2/EGL-3 for cleavage from the larger peptide precursors. A neuroendocrine chaperone 7B2 is needed for the proteolytical activation of proPC2, as extensively studied in mouse models. To determine the role of its orthologue in Caenorhabditis elegans, we analyzed wild-type and 7B2-null strains by HPLC and matrix-assisted laser desorption ionization time-of-flight mass spectrometry, which allowed the identification of a novel neuropeptide gene, flp-33. The presence and/or absence of some neuropeptides in 7B2-null animals strongly differs form the peptide profile in wild-type, suggesting a specific and determined action of 7B2 in C. elegans.