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61.
Jonathan C Fuller Pierre Khoueiry Holger Dinkel Kristoffer Forslund Alexandros Stamatakis Joseph Barry Aidan Budd Theodoros G Soldatos Katja Linssen Abdul Mateen Rajput 《EMBO reports》2013,14(4):302-304
The third Heidelberg Unseminars in Bioinformatics (HUB) was held on 18th October 2012, at Heidelberg University, Germany. HUB brought together around 40 bioinformaticians from academia and industry to discuss the ‘Biggest Challenges in Bioinformatics’ in a ‘World Café’ style event. 相似文献
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Spatial analyses of two color polymorphisms in an alpine grasshopper reveal a role of small‐scale heterogeneity 下载免费PDF全文
Petra Dieker Luisa Beckmann Julia Teckentrup Holger Schielzeth 《Ecology and evolution》2018,8(15):7273-7284
Discrete color polymorphisms represent a fascinating aspect of intraspecific diversity. Color morph ratios often vary clinally, but in some cases, there are no marked clines and mixes of different morphs occur at appreciable frequencies in most populations. This poses the questions of how polymorphisms are maintained. We here study the spatial and temporal distribution of a very conspicuous color polymorphism in the club‐legged grasshopper Gomphocerus sibiricus. The species occurs in a green and a nongreen (predominately brown) morph, a green–brown polymorphism that is common among Orthopteran insects. We sampled color morph ratios at 42 sites across the alpine range of the species and related color morph ratios to local habitat parameters and climatic conditions. Green morphs occurred in both sexes, and their morph ratios were highly correlated among sites, suggesting shared control of the polymorphism in females and males. We found that in at least 40 of 42 sites green and brown morphs co‐occurred with proportions of green ranging from 0% to 70% with significant spatial heterogeneity. The proportion of green individuals tended to increase with decreasing summer and winter precipitations. Nongreen individuals can be further distinguished into brown and pied individuals, and again, this polymorphism is shared with other grasshopper species. We found pied individuals at all sites with proportions ranging from 3% to 75%, with slight, but significant variation between years. Pied morphs show a clinal increase in frequency from east to west and decreased with altitude and lower temperatures and were more common on grazed sites. The results suggest that both small‐scale and large‐scale spatial heterogeneity affects color morph ratios. The almost universal co‐occurrence of all three color morphs argues against strong effects of genetic drift. Instead, the data suggest that small‐scale migration–selection balance and/or local balancing selection maintain populations polymorphic. 相似文献
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Legall H Stiel H Beck M Leupold D Gruszecki WI Lokstein H 《Journal of biochemical and biophysical methods》2007,70(3):369-376
Peridinin-chlorophyll a protein (PCP) is a unique water soluble antenna complex that employs the carotenoid peridinin as the main light-harvesting pigment. In the present study the near edge X-ray absorption fine structure (NEXAFS) spectrum of PCP was recorded at the carbon K-edge. Additionally, the NEXAFS spectra of the constituent pigments, chlorophyll a and peridinin, were measured. The energies of the lowest unoccupied molecular levels of these pigments appearing in the carbon NEXAFS spectrum were resolved. Individual contributions of the pigments and the protein to the measured NEXAFS spectrum of PCP were determined using a “building block” approach combining NEXAFS spectra of the pigments and the amino acids constituting the PCP apoprotein. The results suggest that absorption changes of the pigments in the carbon near K-edge region can be resolved following excitation using a suitable visible pump laser pulse. Consequently, it may be possible to study excitation energy transfer processes involving “optically dark” states of carotenoids in pigment-protein complexes by soft X-ray probe optical pump double resonance spectroscopy (XODR). 相似文献
67.
Effects of common atopy-associated amino acid substitutions in the IL-4 receptor alpha chain on IL-4 induced phenotypes 总被引:3,自引:1,他引:3
Franjkovic I Gessner A König I Kissel K Bohnert A Hartung A Ohly A Ziegler A Hackstein H Bein G 《Immunogenetics》2005,56(11):808-817
The human IL-4 receptor alpha chain gene (IL4R) is highly polymorphic and controversial reports have been published with respect to the association of different single nucleotide polymorphisms (SNPs) with atopy markers. Here we analyzed the functional and associational relevance of common IL4R coding SNPs. Transfection of B cell lines expressing the IL-4R variant V75+R576 did not result in enhanced IL-4 induced CD23 expression compared to cell lines expressing the wild type IL-4R alpha chain. Transfection of the IL-4R variant P503 into a murine T cell line did not influence IL-4 induced T-cell proliferation compared to wild type constructs. Analysis of six IL4R coding SNPs (I75V, E400A, C431R, S436L, S503P, Q576R) and common haplotypes (frequency 0.05%) in blood donors (n=300) did not indicate a significant association with elevated serum IgE level. Moreover, the most informative IL4R coding SNPs (I75V, C431R, Q576R) and related two- and three-point haplotypes (frequency 0.05%) were analyzed in a second, extended group of blood donors (n=689). Again, no significant association with elevated serum IgE was detectable. We conclude that common coding SNPs in the IL4R gene are unlikely to contribute significantly to increased IgE levels and variations outside the coding region may influence atopy susceptibility. 相似文献
68.
Considerable knowledge exists about the effect of aluminium (Al) on root vitality, but whether elevated levels of Al affect
soil microorganisms is largely unknown. We thus compared soils from Al-treated and control plots of a field experiment with
respect to microbial and chemical parameters, as well as root growth and vitality. The field experiment was established in
a 50-year-old Norway spruce (Picea abies L.) stand where no Al or low concentrations of Al had been added every 7–10 days during the growth season for 7 years. Analysis
of soil solutions collected using zero tension lysimeters and porous suction cups showed that Al treatment lead to increased
concentrations of Al, Ca and Mg and lower pH and [Ca + Mg + K/Al] molar ratio. Corresponding soil analyses showed that soil
pH remained unaffected (pH 3.8), that exchangeable Al increased, while exchangeable Ca and Mg decreased due to the Al treatment.
Root in-growth into cores placed in the upper 20 cm of the soil during three growth seasons was not affected by Al additions,
neither was nutrient concentration or mortality of these roots. The biomass of some taxonomic groups of soil microorganisms,
analyzed using specific membrane components (phospholipid fatty acids; PLFAs), was clearly affected by the imposed Al treatment,
both in the organic soil horizon and in the underlying mineral soil. Microbial community structure in both horizons was also
clearly modified by the Al treatment. Shifts in PLFA trans/cis ratios indicative of short term physiological stress were not observed. Yet, aluminium stress was indicated both by changes
in community structure and in ratios of single PLFAs for treated/untreated plots. Thus, soil microorganisms were more sensitive
indicators of subtle chemical changes in soil than chemical composition and vitality of roots. 相似文献
69.
Giavalisco P Li Y Matthes A Eckhardt A Hubberten HM Hesse H Segu S Hummel J Köhl K Willmitzer L 《The Plant journal : for cell and molecular biology》2011,68(2):364-376
The unbiased and comprehensive analysis of metabolites in any organism presents a major challenge if proper peak annotation and unambiguous assignment of the biological origin of the peaks are required. Here we provide a comprehensive multi-isotope labelling-based strategy using fully labelled (13) C, (15) N and (34) S plant tissues, in combination with a fractionated metabolite extraction protocol. The extraction procedure allows for the simultaneous extraction of polar, semi-polar and hydrophobic metabolites, as well as for the extraction of proteins and starch. After labelling and extraction, the metabolites and lipids were analysed using a high-resolution mass spectrometer providing accurate MS and all-ion fragmentation data, providing an unambiguous readout for every detectable isotope-labelled peak. The isotope labelling assisted peak annotation process employed can be applied in either an automated database-dependent or a database-independent analysis of the plant polar metabolome and lipidome. As a proof of concept, the developed methods and technologies were applied and validated using Arabidopsis thaliana leaf and root extracts. Along with a large repository of assigned elemental compositions, which is provided, we show, using selected examples, the accuracy and reliability of the developed workflow. 相似文献
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