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Genetic dissection of sex determinism, inflorescence morphology and downy mildew resistance in grapevine 总被引:1,自引:0,他引:1
Elisa Marguerit Christophe Boury Aurélie Manicki Martine Donnart Gisèle Butterlin Alice Némorin Sabine Wiedemann-Merdinoglu Didier Merdinoglu Nathalie Ollat Stéphane Decroocq 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(7):1261-1278
A genetic linkage map of grapevine was constructed using a pseudo-testcross strategy based upon 138 individuals derived from
a cross of Vitis vinifera Cabernet Sauvignon × Vitis riparia Gloire de Montpellier. A total of 212 DNA markers including 199 single sequence repeats (SSRs), 11 single strand conformation
polymorphisms (SSCPs) and two morphological markers were mapped onto 19 linkage groups (LG) which covered 1,249 cM with an
average of 6.7 cM between markers. The position of SSR loci in the maps presented here is consistent with the genome sequence.
Quantitative traits loci (QTLs) for several traits of inflorescence and flower morphology, and downy mildew resistance were
investigated. Two novel QTLs for downy mildew resistance were mapped on linkage groups 9 and 12, they explain 26.0–34.4 and
28.9–31.5% of total variance, respectively. QTLs for inflorescence morphology with a large effect (14–70% of total variance
explained) were detected close to the Sex locus on LG 2. The gene of the enzyme 1-aminocyclopropane-1-carboxylic acid synthase, involved in melon male organ development
and located in the confidence interval of all QTLs detected on the LG 2, could be considered as a putative candidate gene
for the control of sexual traits in grapevine. Co-localisations were found between four QTLs, detected on linkage groups 1,
14, 17 and 18, and the position of the floral organ development genes GIBBERELLIN INSENSITIVE1, FRUITFULL, LEAFY and AGAMOUS. Our results demonstrate that the sex determinism locus also determines both flower and inflorescence morphological traits. 相似文献
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Gregory M. Raner Jonathan I. Thompson Alice Haddy Valary Tangham Nicole Bynum G. Ramachandra Reddy David P. Ballou John H. Dawson 《Journal of inorganic biochemistry》2006,100(12):2045
Rapid mixing of substrate-free ferric cytochrome P450BM3–F87G with m-chloroperoxybenzoic acid (mCPBA) resulted in the sequential formation of two high-valent intermediates. The first was spectrally similar to compound I species reported previously for P450CAM and CYP 119 using mCPBA as an oxidant, and it featured a low intensity Soret absorption band characterized by shoulder at 370 nm. This is the first direct observation of a P450 compound I intermediate in a type II P450 enzyme. The second intermediate, which was much more stable at pH values below 7.0, was characterized by an intense Soret absorption peak at 406 nm, similar to that seen with P450CAM [T. Spolitak, J.H. Dawson, D.P. Ballou, J. Biol. Chem. 280 (2005) 20300–20309]. Double mixing experiments in which NADPH was added to the transient 406 nm-absorbing intermediate resulted in rapid regeneration of the resting ferric state, with the flavins of the flavoprotein domain in their reduced state. EPR results were consistent with this stable intermediate species being a cytochrome c peroxidase compound ES-like species containing a protein-based radical, likely localized on a nearby Trp or Tyr residue in the active site. Iodosobenzene, peracetic acid, and sodium m-periodate also generated the intermediate at 406 nm, but not the 370 nm intermediate, indicating a probable kinetic barrier to accumulating compound I in reactions with these oxidants. The P450 ES intermediate has not been previously reported using iodosobenzene or m-periodate as the oxygen donor. 相似文献
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We used a mitochondrial and nuclear DNA phylogeny to evaluate the relationships among all noddies (Anous and Procelsterna, Laridae) and to clarify their classification. The Lesser Noddy Anous tenuirostris and Black Noddy Anous minutus form a pair of closely related sister‐species, as do the Blue Noddy Procelsterna albivitta and Grey Noddy Procelsterna cerulea. Blue and Grey Noddies are embedded within the dark noddies and are the sister‐clade to the Lesser and Black Noddies, indicating that the genus Anous in its current definition is not monophyletic. Thus, we propose to merge all noddies into the genus Anous Stephens 1826 , and to consider Procelsterna Lafresnaye 1842 as a junior synonym. 相似文献
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Background
One of the most debated issues in the cognitive neuroscience of language is whether distinct semantic domains are differentially represented in the brain. Clinical studies described several anomic dissociations with no clear neuroanatomical correlate. Neuroimaging studies have shown that memory retrieval is more demanding for proper than common nouns in that the former are purely arbitrary referential expressions. In this study a semantic relatedness paradigm was devised to investigate neural processing of proper and common nouns.Methodology/Principal Findings
780 words (arranged in pairs of Italian nouns/adjectives and the first/last names of well known persons) were presented. Half pairs were semantically related (“Woody Allen” or “social security”), while the others were not (“Sigmund Parodi” or “judicial cream”). All items were balanced for length, frequency, familiarity and semantic relatedness. Participants were to decide about the semantic relatedness of the two items in a pair. RTs and N400 data suggest that the task was more demanding for common nouns. The LORETA neural generators for the related-unrelated contrast (for proper names) included the left fusiform gyrus, right medial temporal gyrus, limbic and parahippocampal regions, inferior parietal and inferior frontal areas, which are thought to be involved in the conjoined processing a familiar face with the relevant episodic information. Person name was more emotional and sensory vivid than common noun semantic access.Conclusions/Significance
When memory retrieval is not required, proper name access (conspecifics knowledge) is not more demanding. The neural generators of N400 to unrelated items (unknown persons and things) did not differ as a function of lexical class, thus suggesting that proper and common nouns are not treated differently as belonging to different grammatical classes. 相似文献48.
Martin B Banz A Bienvenu B Cordier C Dautigny N Bécourt C Lucas B 《Journal of immunology (Baltimore, Md. : 1950)》2004,172(6):3391-3398
CD4+CD25+ regulatory T cells have been extensively studied during the last decade, but how these cells exert their regulatory function on pathogenic effector T cells remains to be elucidated. Naive CD4+ T cells transferred into T cell-deficient mice strongly expand and rapidly induce inflammatory bowel disease (IBD). Onset of this inflammatory disorder depends on IFN-gamma production by expanding CD4+ T cells. Coinjection of CD4+CD25+ regulatory T cells protects recipient mice from IBD. In this study, we show that CD4+CD25+ regulatory T cells do not affect the initial activation/proliferation of injected naive T cells as well as their differentiation into Th1 effectors. Moreover, naive T cells injected together with CD4+CD25+ regulatory T cells into lymphopenic hosts are still able to respond to stimuli in vitro when regulatory T cells are removed. In these conditions, they produce as much IFN-gamma as before injection or when injected alone. Finally, when purified, they are able to induce IBD upon reinjection into lymphopenic hosts. Thus, prevention of IBD by CD4+CD25+ regulatory T cells is not due to deletion of pathogenic T cells, induction of a non reactive state (anergy) among pathogenic effector T cells, or preferential induction of Th2 effectors rather than Th1 effectors; rather, it results from suppression of T lymphocyte effector functions, leading to regulated responses to self. 相似文献
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Daniella Bezerra Duarte Lucas Alexandre Vanderlei Raianne Kívia de Azevêdo Bispo Maria Eliete Pinheiro Geraldo Bezerra da Silva Junior Alice Maria Costa Martins Gdayllon Cavalcante Meneses Elizabeth De Francesco Daher 《PloS one》2014,9(12)