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Furlan Lopes Cassiane Lemos Costa Alice Dionísio Jaqueline Fernanda Delgado Cañedo Andres da Rosa Renata Del Valle Garnero Analia Inacio Ribeiro José Ricardo Gunski Ricardo José 《Genetica》2022,150(5):235-246
Genetica - Known as "electric-light bugs", belostomatids potentially act as agents of biological control. The Belostoma genus has holokinetic chromosomes, interspecific variation in... 相似文献
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Heike I. Rsner Martina Caldarini Gregory Potel Daniel Malmodin Maria A. Vanoni Alessandro Aliverti Ricardo A. Broglia Birthe B. Kragelund Guido Tiana 《Proteins》2022,90(1):96-109
The denatured state of several proteins has been shown to display transient structures that are relevant for folding, stability, and aggregation. To detect them by nuclear magnetic resonance (NMR) spectroscopy, the denatured state must be stabilized by chemical agents or changes in temperature. This makes the environment different from that experienced in biologically relevant processes. Using high-resolution heteronuclear NMR spectroscopy, we have characterized several denatured states of a monomeric variant of HIV-1 protease, which is natively structured in water, induced by different concentrations of urea, guanidinium chloride, and acetic acid. We have extrapolated the chemical shifts and the relaxation parameters to the denaturant-free denatured state at native conditions, showing that they converge to the same values. Subsequently, we characterized the conformational properties of this biologically relevant denatured state under native conditions by advanced molecular dynamics simulations and validated the results by comparison to experimental data. We show that the denatured state of HIV-1 protease under native conditions displays rich patterns of transient native and non-native structures, which could be of relevance to its guidance through a complex folding process. 相似文献
65.
Jada Benn Torres Victoria Martucci Melinda C. Aldrich Miguel G. Vilar Taryn MacKinney Muhammad Tariq Jill B. Gaieski Ricardo Bharath Hernandez Zoila E. Browne Marlon Stevenson Wendell Walters Theodore G. Schurr The Genographic Consortium 《American journal of physical anthropology》2019,169(3):482-497
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Gunnar Sturm Katrin Richter Andreas Doetsch Heinrich Heide Ricardo O Louro Johannes Gescher 《The ISME journal》2015,9(8):1802-1811
Microorganisms show an astonishing versatility in energy metabolism. They can use a variety of different catabolic electron acceptors, but they use them according to a thermodynamic hierarchy, which is determined by the redox potential of the available electron acceptors. This hierarchy is reflected by a regulatory machinery that leads to the production of respiratory chains in dependence of the availability of the corresponding electron acceptors. In this study, we showed that the γ-proteobacterium Shewanella oneidensis produces several functional electron transfer chains simultaneously. Furthermore, these chains are interconnected, most likely with the aid of c-type cytochromes. The cytochrome pool of a single S. oneidensis cell consists of ca. 700 000 hemes, which are reduced in the absence on an electron acceptor, but can be reoxidized in the presence of a variety of electron acceptors, irrespective of prior growth conditions. The small tetraheme cytochrome (STC) and the soluble heme and flavin containing fumarate reductase FccA have overlapping activity and appear to be important for this electron transfer network. Double deletion mutants showed either delayed growth or no growth with ferric iron, nitrate, dimethyl sulfoxide or fumarate as electron acceptor. We propose that an electron transfer machinery that is produced irrespective of a thermodynamic hierarchy not only enables the organism to quickly release catabolic electrons to a variety of environmental electron acceptors, but also offers a fitness benefit in redox-stratified environments. 相似文献
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Selene Báez Agustina Malizia Julieta Carilla Cecilia Blundo Manuel Aguilar Nikolay Aguirre Zhofre Aquirre Esteban álvarez Francisco Cuesta álvaro Duque William Farfán-Ríos Karina García-Cabrera Ricardo Grau Jürgen Homeier Reynaldo Linares-Palomino Lucio R. Malizia Omar Melo Cruz Oriana Osinaga Oliver L. Phillips Carlos Reynel Miles R. Silman Kenneth J. Feeley 《PloS one》2015,10(5)
General patterns of forest dynamics and productivity in the Andes Mountains are poorly characterized. Here we present the first large-scale study of Andean forest dynamics using a set of 63 permanent forest plots assembled over the past two decades. In the North-Central Andes tree turnover (mortality and recruitment) and tree growth declined with increasing elevation and decreasing temperature. In addition, basal area increased in Lower Montane Moist Forests but did not change in Higher Montane Humid Forests. However, at higher elevations the lack of net basal area change and excess of mortality over recruitment suggests negative environmental impacts. In North-Western Argentina, forest dynamics appear to be influenced by land use history in addition to environmental variation. Taken together, our results indicate that combinations of abiotic and biotic factors that vary across elevation gradients are important determinants of tree turnover and productivity in the Andes. More extensive and longer-term monitoring and analyses of forest dynamics in permanent plots will be necessary to understand how demographic processes and woody biomass are responding to changing environmental conditions along elevation gradients through this century. 相似文献
68.
Fossil‐based comparative analyses reveal ancient marine ancestry erased by extinction in ray‐finned fishes 下载免费PDF全文
The marine‐freshwater boundary is a major biodiversity gradient and few groups have colonised both systems successfully. Fishes have transitioned between habitats repeatedly, diversifying in rivers, lakes and oceans over evolutionary time. However, their history of habitat colonisation and diversification is unclear based on available fossil and phylogenetic data. We estimate ancestral habitats and diversification and transition rates using a large‐scale phylogeny of extant fish taxa and one containing a massive number of extinct species. Extant‐only phylogenetic analyses indicate freshwater ancestry, but inclusion of fossils reveal strong evidence of marine ancestry in lineages now restricted to freshwaters. Diversification and colonisation dynamics vary asymmetrically between habitats, as marine lineages colonise and flourish in rivers more frequently than the reverse. Our study highlights the importance of including fossils in comparative analyses, showing that freshwaters have played a role as refuges for ancient fish lineages, a signal erased by extinction in extant‐only phylogenies. 相似文献
69.
Symptoms induced by transgenic expression of p23 from Citrus tristeza virus in phloem‐associated cells of Mexican lime mimic virus infection without the aberrations accompanying constitutive expression 下载免费PDF全文
Nuria Soler Carmen Fagoaga Carmelo López Pedro Moreno Luis Navarro Ricardo Flores Leandro Peña 《Molecular Plant Pathology》2015,16(4):388-399
Citrus tristeza virus (CTV) is phloem restricted in natural citrus hosts. The 23‐kDa protein (p23) encoded by the virus is an RNA silencing suppressor and a pathogenicity determinant. The expression of p23, or its N‐terminal 157‐amino‐acid fragment comprising the zinc finger and flanking basic motifs, driven by the constitutive 35S promoter of cauliflower mosaic virus, induces CTV‐like symptoms and other aberrations in transgenic citrus. To better define the role of p23 in CTV pathogenesis, we compared the phenotypes of Mexican lime transformed with p23‐derived transgenes from the severe T36 and mild T317 CTV isolates under the control of the phloem‐specific promoter from Commelina yellow mottle virus (CoYMV) or the 35S promoter. Expression of the constructs restricted to the phloem induced a phenotype resembling CTV‐specific symptoms (vein clearing and necrosis, and stem pitting), but not the non‐specific aberrations (such as mature leaf epinasty and yellow pinpoints, growth cessation and apical necrosis) observed when p23 was ectopically expressed. Furthermore, vein necrosis and stem pitting in Mexican lime appeared to be specifically associated with p23 from T36. Phloem‐specific accumulation of the p23Δ158–209(T36) fragment was sufficient to induce the same anomalies, indicating that the region comprising the N‐terminal 157 amino acids of p23 is responsible (at least in part) for the vein clearing, stem pitting and, possibly, vein corking in this host. 相似文献
70.
RNA‐Seq bulked segregant analysis enables the identification of high‐resolution genetic markers for breeding in hexaploid wheat 下载免费PDF全文
Ricardo H. Ramirez‐Gonzalez Vanesa Segovia Nicholas Bird Paul Fenwick Sarah Holdgate Simon Berry Peter Jack Mario Caccamo Cristobal Uauy 《Plant biotechnology journal》2015,13(5):613-624
The identification of genetic markers linked to genes of agronomic importance is a major aim of crop research and breeding programmes. Here, we identify markers for Yr15, a major disease resistance gene for wheat yellow rust, using a segregating F2 population. After phenotyping, we implemented RNA sequencing (RNA‐Seq) of bulked pools to identify single‐nucleotide polymorphisms (SNP) associated with Yr15. Over 27 000 genes with SNPs were identified between the parents, and then classified based on the results from the sequenced bulks. We calculated the bulk frequency ratio (BFR) of SNPs between resistant and susceptible bulks, selecting those showing sixfold enrichment/depletion in the corresponding bulks (BFR > 6). Using additional filtering criteria, we reduced the number of genes with a putative SNP to 175. The 35 SNPs with the highest BFR values were converted into genome‐specific KASP assays using an automated bioinformatics pipeline (PolyMarker) which circumvents the limitations associated with the polyploid wheat genome. Twenty‐eight assays were polymorphic of which 22 (63%) mapped in the same linkage group as Yr15. Using these markers, we mapped Yr15 to a 0.77‐cM interval. The three most closely linked SNPs were tested across varieties and breeding lines representing UK elite germplasm. Two flanking markers were diagnostic in over 99% of lines tested, thus providing a reliable haplotype for marker‐assisted selection in these breeding programmes. Our results demonstrate that the proposed methodology can be applied in polyploid F2 populations to generate high‐resolution genetic maps across target intervals. 相似文献