Avian influenza viruses infect primary human bronchial epithelial cells unconstrained by sialic acid α2,3 residues

Avian influenza viruses (AIV) are an important emerging threat to public health. It is thought that sialic acid (sia) receptors are barriers in cross-species transmission where the binding preferences of AIV and human influenza viruses are sias α2,3 versus α2,6, respectively. In this study, we show that a normal fully differentiated, primary human bronchial epithelial cell model is readily infected by low pathogenic H5N1, H5N2 and H5N3 AIV, which primarily bind to sia α2,3 moieties, and replicate in these cells independent of specific sias on the cell surface. NHBE cells treated with neuraminidase prior to infection are infected by AIV despite removal of sia α2,3 moieties. Following AIV infection, higher levels of IP-10 and RANTES are secreted compared to human influenza virus infection, indicating differential chemokine expression patterns, a feature that may contribute to differences in disease pathogenesis between avian and human influenza virus infections in humans.     

Speciation dynamics in the Australo-Papuan Meliphaga honeyeaters

The Australo-Papuan Meliphaga honeyeaters have diversified over a wide range of habitats and elevational zones and are one of the few regionally known cryptic avian radiations. Using a combined 1580 bp of mitochondrial and nuclear DNA we investigate the species limits, systematic affinities and biogeographic history of Meliphaga. We also investigate the role of spatial sorting mechanisms, including altitudinal replacement and niche partitioning, as mechanisms underlying the adaptive radiation of this group. Phylogenetic analysis indicates that the genus Meliphaga comprises at least 16 species, three more than recognized in current classifications. The genus divides into two clades; the species-poor lewinii group, and the larger analoga group that has diversified into a wider range of vertical, vegetational and elevational niches. The basal division of each clade into an Australian and New Guinean assemblage was likely induced by the formation of the Arafura Sea during the early Pliocene ( approximately 4 MYA) with a single reinvasion of Australia by the open forest species M. gracilis during the early Pleistocene (1.2-1.5 MYA) via intermittent land bridges or island hopping. Most recent sister species were found to replace each other geographically within the same ecological and elevational zone conforming to the classical allopatric mode of speciation. In contrast, M. orientalis (650-1950 m) and M. analoga (0-1100 m) were found to replace each other altitudinally across ecological zones providing empirical support for altitudinal speciation as a mechanism of diversification in a montane avifauna. We find no evidence of sympatric speciation (co-existing sister lineages) and suggest that spatial segregation within the habitat (niche partitioning) is primarily a mechanism enabling more divergent species to coexist.     

Mitigation of cardiovascular toxicity in a series of CSF-1R inhibitors,and the identification of AZD7507

The potent and selective 3-amido-4-anilinoquinoline CSF-1R inhibitor AZ683 suffered from cardiovascular liabilities, which were linked to the off-target activities of the compound and ion channel activity in particular. Less basic and less lipophilic examples from both the quinoline and cinnoline series demonstrated cleaner secondary pharmacology profiles. Cinnoline 31 retained the required potency and oral PK profile, and was progressed through the safety screening cascade to be nominated into development as AZD7507.     

Deep-sea origin and in-situ diversification of chrysogorgiid octocorals

The diversity, ubiquity and prevalence in deep waters of the octocoral family Chrysogorgiidae Verrill, 1883 make it noteworthy as a model system to study radiation and diversification in the deep sea. Here we provide the first comprehensive phylogenetic analysis of the Chrysogorgiidae, and compare phylogeny and depth distribution. Phylogenetic relationships among 10 of 14 currently-described Chrysogorgiidae genera were inferred based on mitochondrial (mtMutS, cox1) and nuclear (18S) markers. Bathymetric distribution was estimated from multiple sources, including museum records, a literature review, and our own sampling records (985 stations, 2345 specimens). Genetic analyses suggest that the Chrysogorgiidae as currently described is a polyphyletic family. Shallow-water genera, and two of eight deep-water genera, appear more closely related to other octocoral families than to the remainder of the monophyletic, deep-water chrysogorgiid genera. Monophyletic chrysogorgiids are composed of strictly (Iridogorgia Verrill, 1883, Metallogorgia Versluys, 1902, Radicipes Stearns, 1883, Pseudochrysogorgia Pante & France, 2010) and predominantly (Chrysogorgia Duchassaing & Michelotti, 1864) deep-sea genera that diversified in situ. This group is sister to gold corals (Primnoidae Milne Edwards, 1857) and deep-sea bamboo corals (Keratoisidinae Gray, 1870), whose diversity also peaks in the deep sea. Nine species of Chrysogorgia that were described from depths shallower than 200 m, and mtMutS haplotypes sequenced from specimens sampled as shallow as 101 m, suggest a shallow-water emergence of some Chrysogorgia species.     

Global biogeography of SAR11 marine bacteria

The ubiquitous SAR11 bacterial clade is the most abundant type of organism in the world's oceans, but the reasons for its success are not fully elucidated. We analysed 128 surface marine metagenomes, including 37 new Antarctic metagenomes. The large size of the data set enabled internal transcribed spacer (ITS) regions to be obtained from the Southern polar region, enabling the first global characterization of the distribution of SAR11, from waters spanning temperatures ?2 to 30°C. Our data show a stable co‐occurrence of phylotypes within both ‘tropical’ (>20°C) and ‘polar’ (<10°C) biomes, highlighting ecological niche differentiation between major SAR11 subgroups. All phylotypes display transitions in abundance that are strongly correlated with temperature and latitude. By assembling SAR11 genomes from Antarctic metagenome data, we identified specific genes, biases in gene functions and signatures of positive selection in the genomes of the polar SAR11—genomic signatures of adaptive radiation. Our data demonstrate the importance of adaptive radiation in the organism's ability to proliferate throughout the world's oceans, and describe genomic traits characteristic of different phylotypes in specific marine biomes.     

Molecular phylogenetics and diversification within one of the most geographically variable bird species complexes Pachycephala pectoralis/melanura

The golden‐mangrove whistler complex Pachycephala pectoralis/melanura is, with 66 named populations, described as the most complex avian example of geographic variation in the World. It represents a well‐known example of niche differentiation where one species P. pectoralis is found on faunistically rich larger islands (and mainland) and the other P. melanura is confined to adjacent, faunistically poor islets. Except for a comparison of some Solomon Island populations, the relationships among these taxa have not been tested using molecular data. Here we combine a dense taxon sampling (22 populations of 12 named taxa distributed east of New Guinea and in Australia), with molecular data (two nuclear and two mitochondrial markers) to unravel more of the evolutionary history behind the golden whistler complex. In particular we examine relationships between Pachycephala melanura, and the very similar‐looking P. citreogaster (Bismarcks Islands) and P. pectoralis (Australia). We demonstrate that a well‐supported group of golden whistlers inhabit the Bismarck Islands and that several small islets in the immediate vicinity are inhabited by another monophyletic group consisting of P. melanura, mangrove golden whistler.     

Polyphyletic origin of toxic Pitohui birds suggests widespread occurrence of toxicity in corvoid birds

Pitohui birds from New Guinea have been found to contain a toxin otherwise only found in neotropical poison arrow frogs. Pitohuis have been considered to be monophyletic and thus toxicity is thought to have evolved once in birds. Here, we show that Pitohuis, rather than being a tight-knit group, are polyphyletic and represent several lineages among the corvoid families of passerine birds. This finding demonstrates that the ability to be toxic is widespread among corvoid birds and suggests that additional members of this radiation, comprising more than 700 species, could prove to be toxic. It is postulated that toxic birds ingest the toxin through their insect diet and excrete it through the uropygial gland, from where it is applied to the skin and feathers. Thus, the ability to become toxic is most likely an ancestral condition but variation in diet determines the extent to which toxicity is expressed among corvoid birds. Variability in toxicity levels further suggests that the main function of the toxin is that of a deterrent against ectoparasites and bacterial infection rather than being a defence against predators as initially proposed.     

Two new species of Hyalella from Lake Titicaca,and redescriptions of four others in the genus (Crustacea: Amphipoda)

The amphipod genus Hyalella has its highest diversity in the Andean Lake Titicaca. This genus is the only epigean amphipod present in South America. Eleven endemic and one non-endemic species are known from Lake Titicaca. An additional endemic species, Hyalella nefrens n. sp. and one non-endemic species Hyalella tiwanaku n. sp. are described here. Hyalella cuprea(Faxon, 1876), Hyalella latimanus (Faxon, 1876), Hyalella montforti Chevreux, 1907, and Hyalella neveulemairei Chevreux, 1904 are redescribed. The high diversity of Hyalella in the lake is not well understood, and it has been compared with the spectacular diversity of Lake Baikal.     

Effects of excluding bottom-disturbing mobile fishing gear on abundance and biomass of groundfishes in the Stellwagen Bank National Marine Sanctuary, USA

The Stellwagen Bank National Marine Sanctuary (southern Gulf of Maine, northwest Atlantic) is partially overlapped by the Western Gulf of Maine Closure Area (WGMCA). This is a region in which mobile, bottom-disturbing fishing gear has been banned by the New England Fishery Management Council to facilitate the rebuilding of depleted groundfish populations. We assessed the effects and effectiveness of the WGMCA on groundfish assemblages using habitat-stratified (gravel, sand, mixed benthic habitats) sampling by means of a commercial trawler, inside and outside of the WGMCA. Sampling occurred over three month-long sampling periods in 2004-2005, two during the spring seasons and one during the fall season. A total of 18 species were analyzed for protection effects. After controlling for substratum, location and sampling season, eight groundfish species exhibited higher mean proportional abundance inside than outside the WGMCA while two were proportionally more abundant on average outside of the closure. Four species had higher mean proportional biomasses on average inside the closure and three outside. We conclude that the WGMCA may be achieving its goal of rebuilding abundance and biomass for some commercially targeted groundfishes but not all. This study, six to seven years post-closure establishment, reveals fine-scale spatial and taxonomic complexity which will require a very different monitoring protocol than the one currently in place if adaptive management is to be successful in the region [Current Zoology 56 (1): 134-143, 2010].