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991.
Infection of the brown alga Ectocarpus siliculosus by the oomycete Eurychasma dicksonii induces oxidative stress and halogen metabolism
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992.
Phylogenomics and historical biogeography of the monocot order Liliales: out of Australia and through Antarctica
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![点击此处可从《Cladistics : the international journal of the Willi Hennig Society》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Thomas J. Givnish Alejandro Zuluaga Isabel Marques Vivienne K. Y. Lam Marybel Soto Gomez William J. D. Iles Mercedes Ames Daniel Spalink Jackson R. Moeller Barbara G. Briggs Stephanie P. Lyon Dennis W. Stevenson Wendy Zomlefer Sean W. Graham 《Cladistics : the international journal of the Willi Hennig Society》2016,32(6):581-605
We present the first phylogenomic analysis of relationships among all ten families of Liliales, based on 75 plastid genes from 35 species in 29 genera, and 97 additional plastomes stratified across angiosperm lineages. We used a supermatrix approach to extend our analysis to 58 of 64 genera of Liliales, and calibrated the resulting phylogeny against 17 fossil dates to produce a new timeline for monocot evolution. Liliales diverged from other monocots 124 Mya and began splitting into separate families 113 Mya. Our data support an Australian origin for Liliales, with close relationships between three pairs of lineages (Corsiaceae/Campynemataceae, Philesiaceae/Ripogonaceae, tribes Alstroemerieae/Luzuriageae) in South America and Australia or New Zealand reflecting teleconnections of these areas via Antarctica. Long‐distance dispersal (LDD) across the Pacific and Tasman Sea led to re‐invasion of New Zealand by two lineages (Luzuriaga, Ripogonum); LDD allowed Campynemanthe to colonize New Caledonia after its submergence until 37 Mya. LDD permitted Colchicaceae to invade East Asia and Africa from Australia, and re‐invade Africa from Australia. Periodic desert greening permitted Gloriosa and Iphigenia to colonize Southeast Asia overland from Africa, and Androcymbium–Colchicum to invade the Mediterranean from South Africa. Melanthiaceae and Liliaceae crossed the Bering land‐bridge several times from the Miocene to the Pleistocene. 相似文献
993.
Paul R. Lintott Kate Barlow Nils Bunnefeld Philip Briggs Clara Gajas Roig Kirsty J. Park 《Ecology and evolution》2016,6(7):2044-2052
Urbanization is a key global driver in the modification of land use and has been linked to population declines even in widespread and relatively common species. Cities comprise a complex assortment of habitat types yet we know relatively little about the effects of their composition and spatial configuration on species distribution. Although many bat species exploit human resources, the majority of species are negatively impacted by urbanization. Here, we use data from the National Bat Monitoring Programme, a long‐running citizen science scheme, to assess how two cryptic European bat species respond to the urban landscape. A total of 124 × 1 km2 sites throughout Britain were surveyed. The landscape surrounding each site was mapped and classified into discrete biotope types (e.g., woodland). Generalized linear models were used to assess differences in the response to the urban environment between the two species, and which landscape factors were associated with the distributions of P. pipistrellus and P. pygmaeus. The relative prevalence of P. pygmaeus compared to P. pipistrellus was greater in urban landscapes with a higher density of rivers and lakes, whereas P. pipistrellus was frequently detected in landscapes comprising a high proportion of green space (e.g., parklands). Although P. pipistrellus is thought to be well adapted to the urban landscape, we found a strong negative response to urbanization at a relatively local scale (1 km), whilst P. pygmaeus was detected more regularly in wooded urban landscapes containing freshwater. These results show differential habitat use at a landscape scale of two morphologically similar species, indicating that cryptic species may respond differently to anthropogenic disturbance. Even species considered relatively common and well adapted to the urban landscape may respond negatively to the built environment highlighting the future challenges involved in maintaining biodiversity within an increasingly urbanized world. 相似文献
994.
Sarah J Spencer Manu V Tamminen Sarah P Preheim Mira T Guo Adrian W Briggs Ilana L Brito David A Weitz Leena K Pitk?nen Francois Vigneault Marko PJuhani Virta Eric J Alm 《The ISME journal》2016,10(2):427-436
Many microbial communities are characterized by high genetic diversity. 16S ribosomal RNA sequencing can determine community members, and metagenomics can determine the functional diversity, but resolving the functional role of individual cells in high throughput remains an unsolved challenge. Here, we describe epicPCR (Emulsion, Paired Isolation and Concatenation PCR), a new technique that links functional genes and phylogenetic markers in uncultured single cells, providing a throughput of hundreds of thousands of cells with costs comparable to one genomic library preparation. We demonstrate the utility of our technique in a natural environment by profiling a sulfate-reducing community in a freshwater lake, revealing both known sulfate reducers and discovering new putative sulfate reducers. Our method is adaptable to any conserved genetic trait and translates genetic associations from diverse microbial samples into a sequencing library that answers targeted ecological questions. Potential applications include identifying functional community members, tracing horizontal gene transfer networks and mapping ecological interactions between microbial cells. 相似文献
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Identification of novel pro-alpha2(IX) collagen gene mutations in two families with distinctive oligo-epiphyseal forms of multiple epiphyseal dysplasia.
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P Holden E G Canty G R Mortier B Zabel J Spranger A Carr M E Grant J A Loughlin M D Briggs 《American journal of human genetics》1999,65(1):31-38
Multiple epiphyseal dysplasia (MED) is a genetically heterogeneous disorder with marked clinical and radiographic variability. Traditionally, the mild "Ribbing" and severe "Fairbank" types have been used to define a broad phenotypic spectrum. Mutations in the gene encoding cartilage oligomeric-matrix protein have been shown to result in several types of MED, whereas mutations in the gene encoding the alpha2 chain of type IX collagen (COL9A2) have so far been found only in two families with the Fairbank type of MED. Type IX collagen is a heterotrimer of pro-alpha chains derived from three distinct genes-COL9A1, COL9A2, and COL9A3. In this article, we describe two families with distinctive oligo-epiphyseal forms of MED, which are heterozygous for different mutations in the COL9A2 exon 3/intron 3 splice-donor site. Both of these mutations result in the skipping of exon 3 from COL9A2 mRNA, but the position of the mutation in the splice-donor site determines the stability of the mRNA produced from the mutant COL9A2 allele. 相似文献
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