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Thatjana Gardeitchik Miski Mohamed Benedetta Ruzzenente Daniela Karall Sergio Guerrero-Castillo Daisy Dalloyaux Mariël van den Brand Sanne van Kraaij Ellyze van Asbeck Zahra Assouline Marlene Rio Pascale de Lonlay Sabine Scholl-Buergi David F.G.J. Wolthuis Alexander Hoischen Richard J. Rodenburg Wolfgang Sperl Zsolt Urban Eva Morava 《American journal of human genetics》2018,102(4):685-695
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Anthony Drecourt Joël Babdor Michael Dussiot Floriane Petit Nicolas Goudin Meriem Garfa-Traoré Florence Habarou Christine Bole-Feysot Patrick Nitschké Chris Ottolenghi Metodi D. Metodiev Valérie Serre Isabelle Desguerre Nathalie Boddaert Olivier Hermine Arnold Munnich Agnès Rötig 《American journal of human genetics》2018,102(2):266-277
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Sequence variation in nuclear ribosomal small subunit,internal transcribed spacer and large subunit regions of Rhizophagus irregularis and Gigaspora margarita is high and isolate‐dependent 下载免费PDF全文
Odile Thiéry Martti Vasar Teele Jairus John Davison Christophe Roux Paula‐Ann Kivistik Andres Metspalu Lili Milani Ülle Saks Mari Moora Martin Zobel Maarja Öpik 《Molecular ecology》2016,25(12):2816-2832
Arbuscular mycorrhizal (AM) fungi are known to exhibit high intra‐organism genetic variation. However, information about intra‐ vs. interspecific variation among the genes commonly used in diversity surveys is limited. Here, the nuclear small subunit (SSU) rRNA gene, internal transcribed spacer (ITS) region and large subunit (LSU) rRNA gene portions were sequenced from 3 to 5 individual spores from each of two isolates of Rhizophagus irregularis and Gigaspora margarita. A total of 1482 Sanger sequences (0.5 Mb) from 239 clones were obtained, spanning ~4370 bp of the ribosomal operon when concatenated. Intrasporal and intra‐isolate sequence variation was high for all three regions even though variant numbers were not exhausted by sequencing 12–40 clones per isolate. Intra‐isolate nucleotide variation levels followed the expected order of ITS > LSU > SSU, but the values were strongly dependent on isolate identity. Single nucleotide polymorphism (SNP) densities over 4 SNP/kb in the ribosomal operon were detected in all four isolates. Automated operational taxonomic unit picking within the sequence set of known identity overestimated species richness with almost all cut‐off levels, markers and isolates. Average intraspecific sequence similarity values were 99%, 96% and 94% for amplicons in SSU, LSU and ITS, respectively. The suitability of the central part of the SSU as a marker for AM fungal community surveys was further supported by its level of nucleotide variation, which is similar to that of the ITS region; its alignability across the entire phylum; its appropriate length for next‐generation sequencing; and its ease of amplification in single‐step PCR. 相似文献
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Invasion history and demographic processes associated with rapid morphological changes in the Red‐whiskered bulbul established on tropical islands 下载免费PDF全文
Ariane Le Gros Philippe Clergeau Dario Zuccon Raphaël Cornette Blake Mathys Sarah Samadi 《Molecular ecology》2016,25(21):5359-5376
The Red‐whiskered bulbul is a very successful invasive bird species. Morphological differences have been reported among individuals inhabiting the humid and dry coasts of Reunion Island, in a 30‐year‐old population. This suggests a capacity for rapid local adaptation which could explain the general invasive success of this species. However, the origin and invasion history of this population is unknown. It is therefore not possible to establish with certainty the cause of these morphological differences. Here, we investigated the invasion history of populations of Red‐whiskered bulbul established on Reunion Island, Mauritius and Oahu (three geographically similar tropical islands) to assess the link between invasion history and morphological changes in these populations. We first assessed the source(s) of the invasive populations. We then compared the morphology of the individuals between the invasive and native populations and between the dry and humid coasts of invaded islands. Finally, we inferred the invasion history of the invasive populations to investigate the role of neutral processes (e.g. founder effect and drift) on morphology. We found that the invasive populations have a similar origin and that the morphology of the individuals in these populations has diverged in a similar way from the native range, suggesting a convergent adaptation to tropical islands. Like on Reunion, we found differences in morphology between the dry and humid coasts on Mauritius. These morphological differences can be explained by invasion history on Reunion but not on Mauritius. Both neutral evolution and adaptation thus shape the morphology of invasive Red‐whiskered bulbuls. 相似文献
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Increasing 3D Matrix Rigidity Strengthens Proliferation and Spheroid Development of Human Liver Cells in a Constant Growth Factor Environment 下载免费PDF全文
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Marlin John Mert Daniël Coenrad la Grange Shaunita Hellouise Rose Willem Heber van Zyl 《Journal of industrial microbiology & biotechnology》2016,43(4):431-440
Xylan represents a major component of lignocellulosic biomass, and its utilization by Saccharomyces cerevisiae is crucial for the cost effective production of ethanol from plant biomass. A recombinant xylan-degrading and xylose-assimilating Saccharomyces cerevisiae strain was engineered by co-expression of the xylanase (xyn2) of Trichoderma reesei, the xylosidase (xlnD) of Aspergillus niger, the Scheffersomyces stipitis xylulose kinase (xyl3) together with the codon-optimized xylose isomerase (xylA) from Bacteroides thetaiotaomicron. Under aerobic conditions, the recombinant strain displayed a complete respiratory mode, resulting in higher yeast biomass production and consequently higher enzyme production during growth on xylose as carbohydrate source. Under oxygen limitation, the strain produced ethanol from xylose at a maximum theoretical yield of ~90 %. This study is one of only a few that demonstrates the construction of a S. cerevisiae strain capable of growth on xylan as sole carbohydrate source by means of recombinant enzymes. 相似文献