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41.
Peter Westermeier Gerhard Wenzel Volker Mohler 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,119(7):1301-1311
Single-nucleotide polymorphisms (SNPs) and insertion–deletions (INDELs) are currently the important classes of genetic markers
for major crop species. In this study, methods for developing SNP markers in rapeseed (Brassica napus L.) and their in silico mapping and use for genotyping are demonstrated. For the development of SNP and INDEL markers, 181
fragments from 121 different gene sequences spanning 86 kb were examined. A combination of different selection methods (genome-specific
amplification, hetero-duplex analysis and sequence analysis) allowed the detection of 18 singular fragments that showed a
total of 87 SNPs and 6 INDELs between 6 different rapeseed varieties. The average frequency of sequence polymorphism was estimated
to be one SNP every 247 bp and one INDEL every 3,583 bp. Most SNPs and INDELs were found in non-coding regions. Polymorphism
information content values for SNP markers ranged between 0.02 and 0.50 in a set of 86 varieties. Using comparative genetics
data for B. napus and Arabidopsis thaliana, an allocation of SNP markers to linkage groups in rapeseed was achieved: a unique location was determined for seven gene
sequences; two and three possible locations were found for six and four sequences, respectively. The results demonstrate the
usefulness of existing genomic resources for SNP discovery in rapeseed. 相似文献
42.
43.
Jeppe Reitan Andersen Imad Zein Gerhard Wenzel Birte Darnhofer Joachim Eder Milena Ouzunova Thomas Lübberstedt 《BMC plant biology》2008,8(1):2
Background
Forage quality of maize is influenced by both the content and structure of lignins in the cell wall. Biosynthesis of monolignols, constituting the complex structure of lignins, is catalyzed by enzymes in the phenylpropanoid pathway. 相似文献44.
Kreykenbohm V Wenzel D Antonin W Atlachkine V von Mollard GF 《European journal of cell biology》2002,81(5):273-280
Two mammalian proteins, vtila and vtilb, are homologous to the yeast Q-SNARE Vtilp which is part of several SNARE complexes in different transport steps. In vitro experiments suggest distinct functions for vtila and vtilb. Here we compared the subcellular localization of endogenous vtila and vtilb by immunofluorescence and immuno-electron microscopy. Both proteins had a distinct but overlapping localization. vtila was found predominantly on the Golgi and the TGN, vtilb mostly on tubules and vesicles in the TGN area and on endosomes. vti1a coimmunoprecipitated with VAMP-4, syntaxin 6, and syntaxin 16. These four SNAREs could assemble into a SNARE complex of conserved structure because one SNARE motif of each subgroup is present. vtila-beta, VAMP-4, syntaxin 6, and syntaxin 16 are coenriched with small synaptic vesicles and with clathrin-coated vesicles isolated from rat brain synaptosomes. Therefore, this SNARE complex may have a role in synaptic vesicle biogenesis or recycling. 相似文献
45.
Comhair SA Gaston BM Ricci KS Hammel J Dweik RA Teague WG Meyers D Ampleford EJ Bleecker ER Busse WW Calhoun WJ Castro M Chung KF Curran-Everett D Israel E Jarjour WN Moore W Peters SP Wenzel S Hazen SL Erzurum SC;National Heart Lung Blood Institute Severe Asthma Research Program 《PloS one》2011,6(5):e18574
Background
Environmental tobacco smoke (ETS) has adverse effects on the health of asthmatics, however the harmful consequences of ETS in relation to asthma severity are unknown.Methods
In a multicenter study of severe asthma, we assessed the impact of ETS exposure on morbidity, health care utilization and lung functions; and activity of systemic superoxide dismutase (SOD), a potential oxidative target of ETS that is negatively associated with asthma severity.Findings
From 2002–2006, 654 asthmatics (non-severe 366, severe 288) were enrolled, among whom 109 non-severe and 67 severe asthmatics were routinely exposed to ETS as ascertained by history and validated by urine cotinine levels. ETS-exposure was associated with lower quality of life scores; greater rescue inhaler use; lower lung function; greater bronchodilator responsiveness; and greater risk for emergency room visits, hospitalization and intensive care unit admission. ETS-exposure was associated with lower levels of serum SOD activity, particularly in asthmatic women of African heritage.Interpretation
ETS-exposure of asthmatic individuals is associated with worse lung function, higher acuity of exacerbations, more health care utilization, and greater bronchial hyperreactivity. The association of diminished systemic SOD activity to ETS exposure provides for the first time a specific oxidant mechanism by which ETS may adversely affect patients with asthma. 相似文献46.
G. Schwarz W. Michalek V. Mohler G. Wenzel A. Jahoor 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(3-4):521-530
The complex Mla locus of barley determines resistance to the powdery mildew pathogen Erysiphe graminis f. sp. hordei. With a view towards gene isolation, a population consisting of 950 F2 individuals derived from a cross between the near-isogenic lines ‘P01’ (Mla1) and ‘P10’ (Mla12) was used to construct a high-resolution map of the Mla region. A fluorescence-based AFLP technique and bulked segregant analysis were applied to screen for polymorphic, tightly
linked AFLP markers. Three AFLP markers were selected as suitable for a chromosome-landing strategy. One of these AFLP markers
and a closely linked RFLP marker were converted into sequence-specific PCR markers. PCR-based screening of approximately 70 000
yeast artificial chromosome (YAC) clones revealed three identical YACs harbouring the Mla locus. Terminal insert sequences were obtained using inverse PCR. The derived STS marker from the right YAC end-clone was
mapped distal to the Mla locus.
Received: 17 July 1998 / Accepted: 9 August 1998 相似文献
47.
Rep M van der Does HC Meijer M van Wijk R Houterman PM Dekker HL de Koster CG Cornelissen BJ 《Molecular microbiology》2004,53(5):1373-1383
A 12 kDa cysteine-rich protein is secreted by Fusarium oxysporum f. sp. lycopersici during colonization of tomato xylem vessels. Peptide sequences obtained with mass spectrometry allowed identification of the coding sequence. The gene encodes a 32 kDa protein, designated Six1 for secreted in xylem 1. The central part of Six1 corresponds to the 12 kDa protein found in xylem sap of infected plants. A mutant that had gained virulence on a tomato line with the I-3 resistance gene was found to have lost the SIX1 gene along with neighbouring sequences. Transformation of this mutant with SIX1 restored avirulence on the I-3 line. Conversely, deletion of the SIX1 gene in a wild-type strain results in breaking of I-3-mediated resistance. These results suggest that I-3-mediated resistance is based on recognition of Six1 secreted in xylem vessels. 相似文献
48.
Jürgen Beckmann Armin Mehlich Werner Schröder Herbert R. Wenzel Harald Tschesche 《The protein journal》1989,8(1):101-113
The semisynthesis of homologues of aprotinin, the bovine pancreatic trypsin inhibitor, is described. The P1 lysine15 residue was replaced by two methods. The first procedure, which consisted of two enzymatic steps for the incorporation of other amino acids has previously been described. The second approach consisted of six steps of both enzymatic and chemical nature. The modified inhibitor, in which the lysine15-alanine16 peptide bond is hydrolyzed, was used as the starting material. All carboxyl groups of the modified inhibitor were esterified with methanol; the lysine15 methylester group was then selectively hydrolyzed. Afterward, lysine15 itself was split off. Arginine, glutamic acid, methionine, andl-2-aminohexanoic acid (norleucine, Nle) were incorporated using water-soluble carbodiimide combined with an acylation catalyst. The methylester group was used to prevent polymerization. The reactive-site peptide bonds were resynthesized using either chymotrypsin or trypsin. 相似文献
49.
F. Hoffmann G. Wenzel 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1981,60(3):129-133
Summary From a total of 138 green androgenetic rye lines, 25 were fertilized and examined in field tests: 7 were heterozygous and 18 were homozygous. Of the homozygotes, 4 turned out to be selfincompatible, while 14 set seed after selfing. Four characters were analyzed in detail: 100 kernel weight, plant height, ear length, and alkylresorcinol content. Here we present the first approach in prescreening selfcompatible androgenetic doubled-haploid rye plants with the single grain procedure. The usefulness of this method was confirmed by quantitative resorcinol determination in the following generation. Furthermore, it was demonstrated that all the homologues of the alkylresorcinol were equally reduced. For all characters the means of the different anther derived lines exceeded the means of the controls in both directions, to the positive as well as to the negative side. The incorporation of such a haploid breeding step into breeding programs is discussed.Dedicated to Professor Dr. G. Melchers, on the occasion of his 75th birthday, who initiated this work by forming the project-groups Haploide in der Pflanzenzüchtung 相似文献
50.
Template‐free protein structure prediction and quality assessment with an all‐atom free‐energy model
Biophysical forcefields have contributed less than originally anticipated to recent progress in protein structure prediction. Here, we have investigated the selectivity of a recently developed all‐atom free‐energy forcefield for protein structure prediction and quality assessment (QA). Using a heuristic method, but excluding homology, we generated decoy‐sets for all targets of the CASP7 protein structure prediction assessment with <150 amino acids. The decoys in each set were then ranked by energy in short relaxation simulations and the best low‐energy cluster was submitted as a prediction. For four of nine template‐free targets, this approach generated high‐ranking predictions within the top 10 models submitted in CASP7 for the respective targets. For these targets, our de‐novo predictions had an average GDT_S score of 42.81, significantly above the average of all groups. The refinement protocol has difficulty for oligomeric targets and when no near‐native decoys are generated in the decoy library. For targets with high‐quality decoy sets the refinement approach was highly selective. Motivated by this observation, we rescored all server submissions up to 200 amino acids using a similar refinement protocol, but using no clustering, in a QA exercise. We found an excellent correlation between the best server models and those with the lowest energy in the forcefield. The free‐energy refinement protocol may thus be an efficient tool for relative QA and protein structure prediction. Proteins 2009. © 2009 Wiley‐Liss, Inc. 相似文献