Ecotourism disturbance to wildfowl in protected areas: historical, empirical and experimental approaches in the Camargue, Southern France

Ecotourism is becoming very popular, especially in protected areas where wildlife concentrate and is easier to observe, but the consequences of associated disturbance have seldom be quantified other than in the short-term, making the sustainability of this activity untested. We combined a historical, an empirical and an experimental approach to assess the long-, medium- and short-term consequences of disturbance to wintering wildfowl (Anatidae) in a wetland of international importance in the Camargue, Southern France. In the short-term, disturbance made teal (Anas crecca) move away temporarily from observation blinds without leaving the waterbody. Wildfowl fed more after disturbance, disrupting their normal resting activities. In the medium-term, waterbodies with more tourists did not host fewer birds: conversely the most heavily disturbed one hosted the highest wildfowl density. In the long term, wildfowl numbers were not related with the number of visitors. When practiced with appropriate guiding of people, and where appropriate facilities are provided to limit human disturbance as done here, ecotourism may not affect wintering wildfowl other than reversibly in the very short term. The legitimate demand of the public for access, even in fragile protected areas, may therefore be sustainable under some conditions.     

Genetic variation and drought response in two Populus × euramericana genotypes through 2-DE proteomic analysis of leaves from field and glasshouse cultivated plants

Genotype and water deficit effects on leaf 2-DE protein profiles of two Populus deltoides × Populus nigra, cv. ‘Agathe_F’ and ‘Cima’, were analysed over a short-term period of 18 days in glasshouse using 4-month-old rooted cuttings and over a long-lasting period of 86 days in open field using 4-year-old rooted cuttings. Leaf proteomes were analyzed using two-dimensional gel electrophoresis, and proteins were identified after database searching from MS peptide spectra.A reliable genotype effect was observed in the leaf proteome over experiment locations, water regimes and sampling dates. Quantitative differences between genotypes were found. Most of them corresponded to proteins matching isoforms or post-translational modification variants. However, ‘Cima’ displayed the highest abundance of antioxidant enzymes.In response to water deficit, about 10% of the reproducible spots significantly varied regardless of the experiment location, among which about 25% also displayed genotype-dependent variations. As a whole, while ‘Cima’ differed from ‘Agathe_F’ by increased abundance of enzymes involved in photorespiration and in oxidative stress, ‘Agathe_F’ was mainly differentiated by increased abundance of enzymes involved in photosynthesis.     

Histone phosphorylation: how to proceed

Among all posttranslational modifications that occur on histone tails, phosphorylation is the one that establishes a direct link between chromatin remodeling and intracellular signaling pathways. Specific, conserved serine residues are present on the N-terminal tails of each histone. These are phosphoacceptor sites for a number of kinases, whose identification is essential to decipher the transduction routes leading to various physiological responses. In the case of histone H3, phosphorylation at the Ser10 residue may lead to either activated gene expression or chromatin condensation during mitosis. In addition, phosphorylation at specific sites may be coupled to other distinct modifications, such as acetylation and methylation, generating the so-called "histone code" which postulates that well defined combinatorial modifications at histone tails correspond to specific physiological responses. Here we describe a number of experimental methodologies that are essential for the study of histone phosphorylation. While chromatin immunoprecipitation is useful in recognizing gene targets, the in-gel kinase assay is a first, essential step in establishing the identity of the kinase(s) that operates in response to a specific signaling pathway. The subsequent use of in vitro kinase assays is helpful in validating the implication of a candidate kinase. These powerful approaches are important as identification of the signaling transduction routes leading to chromatin remodeling is critical to an understanding of all cellular processes.     

Laparoscopic appendectomy to remove a metallic foreign body in a wild Bornean orangutan (Pongo pygmaeus) undergoing rehabilitation

A laparoscopic appendectomy was performed in a wild orangutan (Pongo pygmaeus) undergoing rehabilitation, for a metal nail found on radiographs, using 3‐mm instrumentation. Post‐operative healing was rapid and uneventful, with return to the forest within 10 days. This is the first report of minimally invasive surgery in a wild orangutan.     

Segmental duplications arise from Pol32-dependent repair of broken forks through two alternative replication-based mechanisms

The propensity of segmental duplications (SDs) to promote genomic instability is of increasing interest since their involvement in numerous human genomic diseases and cancers was revealed. However, the mechanism(s) responsible for their appearance remain mostly speculative. Here, we show that in budding yeast, replication accidents, which are most likely transformed into broken forks, play a causal role in the formation of SDs. The Pol32 subunit of the major replicative polymerase Poldelta is required for all SD formation, demonstrating that SDs result from untimely DNA synthesis rather than from unequal crossing-over. Although Pol32 is known to be required for classical (Rad52-dependant) break-induced replication, only half of the SDs can be attributed to this mechanism. The remaining SDs are generated through a Rad52-independent mechanism of template switching between microsatellites or microhomologous sequences. This new mechanism, named microhomology/microsatellite-induced replication (MMIR), differs from all known DNA double-strand break repair pathways, as MMIR-mediated duplications still occur in the combined absence of homologous recombination, microhomology-mediated, and nonhomologous end joining machineries. The interplay between these two replication-based pathways explains important features of higher eukaryotic genomes, such as the strong, but not strict, association between SDs and transposable elements, as well as the frequent formation of oncogenic fusion genes generating protein innovations at SD junctions.     

Tuberculosis Exacerbates HIV-1 Infection through IL-10/STAT3-Dependent Tunneling Nanotube Formation in Macrophages

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Large-scale patterns of river inputs in southwestern Europe: seasonal and interannual variations and potential eutrophication effects at the coastal zone

We provide data on nutrient export for 28 rivers in southwestern Europe and analyze long-term changes in the context of anthropogenic pressures and regulation policies. Special attention is given to seasonal variations, because the integrated annual values that are usually provided do not allow us to establish comparisons with seasonal phytoplankton dynamics. The eutrophication risk associated with river inputs is addressed by means of an indicator (Index of Coastal Eutrophication Potential, ICEP, Billen and Garnier, Mar Chem 106:148–160, 2007). An overview of the temporal evolution and the intra-annual variability of the ICEP is discussed for specific rivers and integrated coastal regions. The annual dynamics of the eutrophication indicator is analyzed to delimit those periods when the risk of eutrophication is particularly high. The trends in nutrient fluxes and coastal phytoplankton are compared by means of a case study (Seine Bay). The decrease in phosphorus matches a general decrease in phytoplankton biomass in the summer. However, sustained high values of nitrogen still foster the emergence of harmful algal blooms, and we found an increase in the summer abundance of dinoflagellates. The abatement of phosphorus alone is not enough to shortcut harmful blooms and toxic outbreaks in the Seine Bay. A reduction in nitrogen inputs may be necessary to effectively minimize eutrophication problems.