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991.
Christoph Reisch Tobias Windmaißer Frank Vogler Franz Schuhwerk Norbert Meyer 《Botanical journal of the Linnean Society. Linnean Society of London》2015,177(1):112-123
The rare and endangered Hieracium wiesbaurianum species group shows a scattered relictual distribution in Bavaria. Recently, a couple of populations were discovered which clearly differ from all other populations. If these must be considered as taxonomically independent units, they would be of crucial conservation interest, because of the sole responsibility that Bavaria has for these worldwide endemics. We therefore analysed the genetic structure of H. wiesbaurianum in a comparative approach. Our analysis comprised 37 populations of 13 taxa of H. wiesbaurianum, H. bifidum and H. laevigatum, including three potentially new taxa. We applied amplified fragment length polymorphism (AFLP) analysis and observed only limited genetic variation within populations and taxa. Nevertheless, each studied individual exhibited a unique genotype. An analysis of molecular variance revealed high levels of genetic variation between taxa, but populations were genetically less different. The clear genetic differentiation between the studied taxa was supported by neighbor‐joining cluster analyses and principal coordinate analyses in which every individual was clearly assigned to its respective taxon. The three potentially new taxa were genetically as well differentiated as the other taxa included in our study. This supports the assumption that they should be treated as taxonomically independent units of high conservation interest. Therefore, the genetic analysis confirmed the morphologically based classification of the studied Hieracium taxa. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 177 , 112–123. 相似文献
992.
Eduardo Pérez‐Torres Norbert Kirchgessner Johannes Pfeifer Achim Walter 《Plant, cell & environment》2015,38(11):2318-2326
The formation and development of belowground organs is difficult to study. X‐ray computed tomography (CT) provides the possibility to analyse and interpret subtle volumetric changes of belowground organs such as tubers, storage roots and nodules. Here, we report on the establishment of a method based on a voxel dimension of 240 μm and precision (standard deviation) of 30 μL that allows interpreting growth differences among potato tubers happening within 3 h. Plants were not stressed by the application of X‐ray radiation, which was shown both by morphological comparison with control plants and by analysis of lipid peroxidation as a measure of oxidative stress. Diel (24 h) tuber growth fluctuations of three potato genotypes were monitored in soil‐filled pots of 10 L. In contrast to the results from previous reports, most tubers grew at similar rates during day and night. Tuber growth was not related to the developmental stage of plants and tubers. Pronounced differences were observed between average growth rates in different tubers within a plant. These results are discussed in the context of restrictions of past methods to study tuber growth and in the context of their potential for the characterization of the formation and development of other belowground plant organs. 相似文献
993.
Julia Wallmeier Diana Bracht Hessa S. Alsaif Gerard W. Dougherty Heike Olbrich Sandra Cindric Mark Dzietko Christoph Heyer Norbert Teig Charlotte Thiels Eissa Faqeih Aqeela Al-Hashim Sameena Khan Ibrahim Mogarri Mohammed Almannai Wadha Al Otaibi Fowzan S. Alkuraya Cordula Koerner-Rettberg Heymut Omran 《American journal of human genetics》2021,108(7):1318-1329
994.
Olaf Isken Ulrike Langerwisch Robert Sch?nherr Benjamin Lamp Kristin Schr?der Rainer Duden Tillmann H. Rümenapf Norbert Tautz 《Journal of virology》2014,88(1):82-98
Nonstructural protein 5A (NS5A) of bovine viral diarrhea virus (BVDV) is a hydrophilic phosphoprotein with RNA binding activity and a critical component of the viral replicase. In silico analysis suggests that NS5A encompasses three domains interconnected by two low-complexity sequences (LCSs). While domain I harbors two functional determinants, an N-terminal amphipathic helix important for membrane association, and a Zn-binding site essential for RNA replication, the structure and function of the C-terminal half of NS5A are still ill defined. In this study, we introduced a panel of 10 amino acid deletions covering the C-terminal half of NS5A. In the context of a highly efficient monocistronic replicon, deletions in LCS I and the N-terminal part of domain II, as well as in domain III, were tolerated with regard to RNA replication. When introduced into a bicistronic replicon, only deletions in LCS I and the N-terminal part of domain II were tolerated. In the context of the viral full-length genome, these mutations allowed residual virion morphogenesis. Based on these data, a functional monocistronic BVDV replicon coding for an NS5A variant with an insertion of the fluorescent protein mCherry was constructed. Live cell imaging demonstrated that a fraction of NS5A-mCherry localizes to the surface of lipid droplets. Taken together, this study provides novel insights into the functions of BVDV NS5A. Moreover, we established the first pestiviral replicon expressing fluorescent NS5A-mCherry to directly visualize functional viral replication complexes by live cell imaging. 相似文献
995.
996.
Christian Roth Ren Wei Thorsten Oeser Johannes Then Christina Föllner Wolfgang Zimmermann Norbert Sträter 《Applied microbiology and biotechnology》2014,98(18):7815-7823
Bacterial cutinases are promising catalysts for the modification and degradation of the widely used plastic polyethylene terephthalate (PET). The improvement of the enzyme for industrial purposes is limited due to the lack of structural information for cutinases of bacterial origin. We have crystallized and structurally characterized a cutinase from Thermobifida fusca KW3 (TfCut2) in free as well as in inhibitor-bound form. Together with our analysis of the thermal stability and modelling studies, we suggest possible reasons for the outstanding thermostability in comparison to the less thermostable homolog from Thermobifida alba AHK119 and propose a model for the binding of the enzyme towards its polymeric substrate. The TfCut2 structure is the basis for the rational design of catalytically more efficient enzyme variants for the hydrolysis of PET and other synthetic polyesters. 相似文献
997.
Michael J. Kelley Jianxin Shi Bari Ballew Paula L. Hyland Wen-Qing Li Melissa Rotunno David A. Alcorta Norbert J. Liebsch Jason Mitchell Sara Bass David Roberson Joseph Boland Michael Cullen Ji He Laurie Burdette Meredith Yeager Stephen J. Chanock Dilys M. Parry Alisa M. Goldstein Xiaohong R. Yang 《Human genetics》2014,133(10):1289-1297
Chordoma is a rare bone cancer that is believed to originate from notochordal remnants. We previously identified germline T duplication as a major susceptibility mechanism in several chordoma families. Recently, a common genetic variant in T (rs2305089) was significantly associated with the risk of sporadic chordoma. We sequenced all T exons in 24 familial cases and 54 unaffected family members from eight chordoma families (three with T duplications), 103 sporadic cases, and 160 unrelated controls. We also measured T copy number variation in all sporadic cases. We confirmed the association between the previously reported variant rs2305089 and risk of familial [odds ratio (OR) = 2.6, 95 % confidence interval (CI) = 0.93, 7.25, P = 0.067] and sporadic chordoma (OR = 2.85, 95 % CI = 1.89, 4.29, P < 0.0001). We also identified a second common variant, rs1056048, that was strongly associated with chordoma in families (OR = 4.14, 95 % CI = 1.43, 11.92, P = 0.0086). Among sporadic cases, another common variant (rs3816300) was significantly associated with risk when jointly analyzed with rs2305089. The association with rs3816300 was significantly stronger in cases with early age onset. In addition, we identified three rare variants that were only observed among sporadic chordoma cases, all of which have potential functional relevance based on in silico predictions. Finally, we did not observe T duplication in any sporadic chordoma case. Our findings further highlight the importance of the T gene in the pathogenesis of both familial and sporadic chordoma and suggest a complex susceptibility related to T. 相似文献
998.
Christos Stritsis Bernd Steingrobe Norbert Claassen 《International journal of phytoremediation》2014,16(11):1104-1118
Maize, sunflower, flax, and spinach differed in the accumulation of Cd when grown on a Cd contaminated soil. This was mainly due to the different Cd net influx, In , that varied among species by a factor of up to 30. The objective of this study was to find possible reasons for the different Cd In by using a mechanistic model. After 14 days of Cd uptake the model calculated only a small Cd depletion at the root surface, e.g. from 0.22 μmol L?1down to 0.19 μmol L?1for maize and from 0.48 μmol L?1down to 0.35 μmol L?1for spinach. Even so the model always overestimated the Cd In , for spinach by a factor of 1.5 and for maize by a factor of 10. Only simulating a decrease of CLi or the root absorbing power, α, by 40% to 90% gave an agreement of calculated and measured In . This may be interpreted as that about 40% in the case of spinach and 90% in the case of maize of the Cd in soil solution were not accessible for plant uptake. The high sensitivity to α also shows that not the Cd transport to the root but α was limiting the step for Cd uptake. 相似文献
999.
Samia Aci-Sèche Paul Sawma Pierre Hubert James N. Sturgis Dominique Bagnard Laurent Jacob Monique Genest Norbert Garnier 《PloS one》2014,9(5)
The cancer associated class 3 semaphorins require direct binding to neuropilins and association to plexins to trigger cell signaling. Here, we address the role of the transmembrane domains of neuropilin 1 and plexin A1 for the dimerization of the two receptors by characterizing the assembly in lipid bilayers using coarse-grained molecular dynamics simulations. From experimental evidence using a two-hybrid system showing the biochemical association of the two receptors transmembrane domains, we performed molecular simulations in DOPC and POPC demonstrating spontaneously assembly to form homodimers and heterodimers with a very high propensity for right-handed packing of the helices. Inversely, left-handed packing was observed with a very low propensity. This mode of packing was observed uniquely when the plexin A1 transmembrane domain was involved in association. Potential of mean force calculations were used to predict a hierarchy of self-association for the monomers: the two neuropilin 1 transmembrane domains strongly associated, neuropilin 1 and plexin A1 transmembrane domains associated less and the two plexin A1 transmembrane domains weakly but significantly associated. We demonstrated that homodimerization and heterodimerization are driven by GxxxG motifs, and that the sequence context modulates the packing mode of the plexin A1 transmembrane domains. This work presents major advances towards our understanding of membrane signaling platforms assembly through membrane domains and provides exquisite information for the design of antagonist drugs defining a novel class of therapeutic agents. 相似文献
1000.
Anja B?hm Anna Halama Tobias Meile Marty Zdichavsky Rainer Lehmann Cora Weigert Andreas Fritsche Norbert Stefan Alfred K?nigsrainer Hans-Ulrich H?ring Martin Hrabě de Angelis Jerzy Adamski Harald Staiger 《PloS one》2014,9(4)