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Microorganisms often form symbiotic relationships with eukaryotes, and the complexity of these relationships can range from those with one single dominant symbiont to associations with hundreds of symbiont species. Microbial symbionts occupying equivalent niches in different eukaryotic hosts may share functional aspects, and convergent genome evolution has been reported for simple symbiont systems in insects. However, for complex symbiont communities, it is largely unknown how prevalent functional equivalence is and whether equivalent functions are conducted by evolutionarily convergent mechanisms. Sponges represent an evolutionarily divergent group of species with common physiological and ecological traits. They also host complex communities of microbial symbionts and thus are the ideal model to test whether functional equivalence and evolutionary convergence exist in complex symbiont communities across phylogenetically divergent hosts. Here we use a sampling design to determine the phylogenetic and functional profiles of microbial communities associated with six sponge species. We identify common functions in the six microbiomes, demonstrating the existence of functional equivalence. These core functions are consistent with our current understanding of the biological and ecological roles of sponge-associated microorganisms and also provide insight into symbiont functions. Importantly, core functions also are provided in each sponge species by analogous enzymes and biosynthetic pathways. Moreover, the abundance of elements involved in horizontal gene transfer suggests their key roles in the genomic evolution of symbionts. Our data thus demonstrate evolutionary convergence in complex symbiont communities and reveal the details and mechanisms that underpin the process.

Wat zou er gebeuren wanneer we beken zichzelf zouden laten vormen? Wanneer we stuwen verwijderen en stoppen met het onderhoud en beheer? Waterschap Aa en Maas vroeg Oranjewoud, Antea Group België en Bureau Stroming om voor de Graafsche Raam in Oost-Brabant te onderzoeken wat er dan gebeurt en een vergelijking te maken met regulier beekherstel. Uitkomst van het onderzoek was dat aanzienlijk minder grond behoefde te worden aangekocht en dat relatief weinig grondwerk nodig was. Daardoor kan meer worden geïnvesteerd in het beekdal en het samen zoeken naar maatschappelijke acceptatie van de nieuwe, natuurlijke omstandigheden. Conclusie van de onderzoekers is dat deze nieuwe vorm van beekherstel, door het waterschap 'Beekdal in beweging' genoemd, een interessante aanpak is om beken duurzaam te herstellen

About 50% of all known hot subdwarf B stars (sdBs) reside in close (short period) binaries, for which common envelope ejection is the most likely formation mechanism. However, Han et al. 2003 predict that the majority of sdBs should form through stable mass transfer leading to long period binaries. Determining orbital periods for these systems is challenging and while the orbital periods of ~100 short period systems have been measured, there are no periods measured above 30 days. As part of a large program to characterise the orbital periods of subdwarf B binaries and their formation history, we have found that PG1018-047 has an orbital period of 760\pm6 days, easily making it the longest period ever detected for a subdwarf B binary. Exploiting the Balmer lines of the subdwarf primary and the narrow absorption lines of the companion present in the spectra, we derive the radial velocity amplitudes of both stars, and estimate the mass ratio M_{MS}/M_{sdB} = 1.6\pm0.2. From the combination of visual and infrared photometry, the spectral type of the companion star is determined to be mid K., Comment: Submitted for publication in MNRAS, 12 pages, 6 figures, 8 tables

We performed a genome-wide association study of melanoma in a discovery cohort of 2,168 Australian individuals with melanoma and 4,387 control individuals. In this discovery phase, we confirm several previously characterized melanoma-associated loci at MC1R, ASIP and MTAP-CDKN2A. We selected variants at nine loci for replication in three independent case-control studies (Europe: 2,804 subjects with melanoma, 7,618 control subjects; United States 1: 1,804 subjects with melanoma, 1,026 control subjects; United States 2: 585 subjects with melanoma, 6,500 control subjects). The combined meta-analysis of all case-control studies identified a new susceptibility locus at 1q21.3 (rs7412746, P = 9.0 × 10(-11), OR in combined replication cohorts of 0.89 (95% CI 0.85-0.95)). We also show evidence suggesting that melanoma associates with 1q42.12 (rs3219090, P = 9.3 × 10(-8)). The associated variants at the 1q21.3 locus span a region with ten genes, and plausible candidate genes for melanoma susceptibility include ARNT and SETDB1. Variants at the 1q21.3 locus do not seem to be associated with human pigmentation or measures of nevus density.

The pathogen Salmonella Typhimurium is a common cause of diarrhea and invades the gut tissue by injecting a cocktail of virulence factors into epithelial cells, triggering actin rearrangements, membrane ruffling and pathogen entry. One of these factors is SopE, a G-nucleotide exchange factor for the host cellular Rho GTPases Rac1 and Cdc42. How SopE mediates cellular invasion is incompletely understood. Using genome-scale RNAi screening we identified 72 known and novel host cell proteins affecting SopE-mediated entry. Follow-up assays assigned these 'hits' to particular steps of the invasion process; i.e., binding, effector injection, membrane ruffling, membrane closure and maturation of the Salmonella-containing vacuole. Depletion of the COPI complex revealed a unique effect on virulence factor injection and membrane ruffling. Both effects are attributable to mislocalization of cholesterol, sphingolipids, Rac1 and Cdc42 away from the plasma membrane into a large intracellular compartment. Equivalent results were obtained with the vesicular stomatitis virus. Therefore, COPI-facilitated maintenance of lipids may represent a novel, unifying mechanism essential for a wide range of pathogens, offering opportunities for designing new drugs.

Hoe groot is de bijdrage van sportvelden aan de versnelde afvoer van regenwater? Deze vraag wordt steeds vaker gesteld als onderdeel van ruimtelijke procedures en bij het aanvragen van vergunningen in het kader van de Waterwet. De praktijk leert dat waterschappen deze vraag niet eenduidig benaderen. Voor de Branchevereniging Sport en Cultuurtechniek was dit aanleiding naar meer uniformiteit te zoeken. Samen met Oranjewoud is een bruikbare richtlijn gevonden door een vergelijk te trekken tussen het afvoergedrag van sportvelden en dat van verhard oppervlak.

Rijkswaterstaat, de provincie Noord-Brabant en de gemeente Tilburg willen al geruime tijd een deel van het Wilhelminakanaal vergroten en verdiepen. Deze ingreep moet dat deel van het kanaal bevaarbaar maken voor klasse IV-schepen ofwel schepen met een diepgang tot drie meter. De benodigde maatregelen veroorzaken een peilverlaging van het kanaal. Om de gevolgen voor de omgeving en het watersysteem te bepalen, is de watertoetsprocedure doorlopen. Daarbij werd gebruik gemaakt van een model dat Oranjewoud in het kader van het geohydrologisch onderzoek opstelde. Dit artikel beschrijft het watertoetsproces, de manier waarop het geohydrologische model is ingezet en de manier waarop de effecten zijn berekend.

Introduction. This study aimed to estimate the most recent caesarean section rates in the world and examine the association between these rates and old and new indicators of health care. Methods. Authors analyzed the Caesarean Section (CS) rates, also in geo-economic and economic groups, and correlated them to maternal and neonatal mortality, to births attended by skilled health personnel and to births among adolescents. Analysis of covariance and piecewise regressions were used for the statistical analysis. Results. In 47.2% of the countries, the CS rate exceeded 15%. Countries of Latin America and the Caribbean along with Europe, North America and Oceania had the highest values. The analysis showed an inverse association between CS rates and Maternal Mortality (MMR) and Neonatal Mortality (NMR) for all geographical areas except for Europe. The greatest association was observed in lower-middle-income countries. In developing countries only 50% of cases, occur in medical facilities and only half of these are seen by medical, nursing and obstetrical staff. Age of the mother appears to influence the outcome and choice of delivery type. Countries where an high ABR rate is present have low CS use. Conclusions. To best evaluate the consequences of the increasing rate of CS, it would be useful to identify the most sensitive outcome indicators.

An essential prerequisite for any systems-level understanding of cellular functions is to correctly uncover and annotate all functional interactions among proteins in the cell. Toward this goal, remarkable progress has been made in recent years, both in terms of experimental measurements and computational prediction techniques. However, public efforts to collect and present protein interaction information have struggled to keep up with the pace of interaction discovery, partly because protein-protein interaction information can be error-prone and require considerable effort to annotate. Here, we present an update on the online database resource Search Tool for the Retrieval of Interacting Genes (STRING); it provides uniquely comprehensive coverage and ease of access to both experimental as well as predicted interaction information. Interactions in STRING are provided with a confidence score, and accessory information such as protein domains and 3D structures is made available, all within a stable and consistent identifier space. New features in STRING include an interactive network viewer that can cluster networks on demand, updated on-screen previews of structural information including homology models, extensive data updates and strongly improved connectivity and integration with third-party resources. Version 9.0 of STRING covers more than 1100 completely sequenced organisms; the resource can be reached at http://string-db.org.

BACKGROUND: Shotgun sequencing of environmental DNA is an essential technique for characterizing uncultivated microbes in situ. However, the taxonomic and functional assignment of the obtained sequence fragments remains a pressing problem. RESULTS: Existing algorithms are largely optimized for speed and coverage; in contrast, we present here a software framework that focuses on a restricted set of informative gene families, using Maximum Likelihood to assign these with the best possible accuracy. This framework ('MLTreeMap'; http://mltreemap.org/) uses raw nucleotide sequences as input, and includes hand-curated, extensible reference information. CONCLUSIONS: We discuss how we validated our pipeline using complete genomes as well as simulated and actual environmental sequences.