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821.
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
822.
Patricia Ann Okubara Camille M. Steber Victor L. DeMacon Nathalie L. Walter Timothy C. Paulitz Kimberlee K. Kidwell 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,119(2):293-303
The necrotrophic root pathogens Rhizoctonia solani AG-8 and R. oryzae cause Rhizoctonia root rot and damping-off, yield-limiting diseases that pose barriers to the adoption of conservation tillage
in wheat production systems. Existing control practices are only partially effective, and natural genetic resistance to Rhizoctonia has not been identified in wheat or its close relatives. We report the first genetic resistance/tolerance to R. solani AG-8 and R. oryzae in wheat (Triticum aestivum L. em Thell) germplasm ‘Scarlet-Rz1’. Scarlet-Rz1 was derived from the allohexaploid spring wheat cultivar Scarlet using
EMS mutagenesis. Tolerant seedlings displayed substantial root and shoot growth after 14 days in the presence of 100–400 propagules
per gram soil of R. solani AG-8 and R. oryzae in greenhouse assays. BC2F4 individuals of Scarlet-Rz1 showed a high and consistent degree of tolerance. Seedling tolerance was transmissible and appeared
to be dominant or co-dominant. Scarlet-Rz1 is a promising genetic resource for developing Rhizoctonia-tolerant wheat cultivars because the tolerance trait immediately can be deployed into wheat breeding germplasm through cross-hybridization,
thereby avoiding difficulties with transfer from secondary or tertiary relatives as well as constraints associated with genetically
modified plants. Our findings also demonstrate the utility of chemical mutagenesis for generating tolerance to necrotrophic
pathogens in allohexaploid wheat.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
P. A. Okubara and C. M. Steber contributed equally to this work. 相似文献
823.
Julie Cattelotte Nicolas Tournier Nathalie Rizzo-Padoin† Alfred H. Schinkel‡ Jean-Michel Scherrmann Salvatore Cisternino§ 《Journal of neurochemistry》2009,108(3):767-775
Cationic 99m Tc-agents like 99m Tc-hexakis-2-methoxyisobutyl isonitrile (99m Tc-MIBI) cannot be used for brain imaging because they do not enter the brain as readily as some uncharged 99m Tc-compounds. The mechanism by which cationic 99m Tc-agents are transported across the blood–brain barrier (BBB) remains unclear. We explored 99m Tc-MIBI transport by in situ mouse brain perfusion to determine the influence of BBB features like the ATP-binding cassette transporters (Abcb1/P-glycoprotein (P-gp), Abcc1/Mrp1, and Abcg2/Bcrp), organic cation transporters (Slc22a1-3/Oct1-3), the transmembrane potential and the dipole membrane potential. P-gp reduced 99m Tc-MIBI transport across the BBB of P-gp-deficient mice 2.2-fold, as confirmed by PSC833 and GF120918 inhibition. Paradoxically verapamil decreased its transport '0.6-fold'. Reducing the BBB dipole membrane potential with tetraphenylborate or phloretin increased 99m Tc-MIBI transport about 12- and 20-fold, respectively. Guanidine, diphenhydramine, and carnitine significantly decreased 99m Tc-MIBI transport, but tetraethylammonium did not. 99m Tc-MIBI transport at the BBB is restricted by P-gp but not by Mrp1 or Bcrp. Some organic cations reduced the influx of 99m Tc-MIBI into the brain independently of Oct1, 2 and 3, but this could be due to their effect on another cation transporter. The membrane dipole potential of the luminal BBB membrane appeared to be the main factor restricting 99m Tc-MIBI permeability. 相似文献
824.
According to current knowledge, sexual development of the apicomplexan parasite Neospora caninum takes place in the canine intestine. However, to date there is no information on the interaction between the parasite and the canine intestinal epithelium, and, next to the clinical and in vivo research tools, an in vitro model comprised of canine intestinal cells infected with N. caninum would be very helpful for investigations at the cellular level. Following the isolation of cells of neonatal canine duodenum and growth of cell cultures to monolayers for 5-6 days, canine intestinal epithelial cells were exposed to cell culture-derived N. caninum tachyzoites and bradyzoites. The host cells remained viable during in vitro culture for an average of 2 wk. During this time span, N. caninum was found to readily adhere to any surface area of these cells, but infection took mostly place at sites where microvilli-like structures were missing, e.g., at the cell periphery, with tachyzoites exhibiting at least 3-4 times increased invasive capacities compared to bradyzoites. Once intracellular, parasites resided within a parasitophorous vacuole, moved toward the vicinity of the nucleus and the more distal portion of the epithelial cells, and proliferated to form vacuoles of not more than 2-4 parasites, which were surrounded by numerous mitochondria. Immunofluorescence staining and TEM of infected cells showed that the expression of cytokeratins and the structural integrity of desmosomes and tight junctions were not notably altered during infection. Furthermore, no changes could be detected in the alkaline phosphatase activities in cell culture supernatants of infected and noninfected cells. Canine duodenal epithelial cell cultures represent a useful tool for future studies on the characteristics of the intestinal phases of N. caninum infection. 相似文献
825.
826.
827.
Mechanisms to cope with arsenic or cadmium excess in plants 总被引:5,自引:0,他引:5
Nathalie Verbruggen Christian Hermans Henk Schat 《Current opinion in plant biology》2009,12(3):364-372
828.
Slim Abdelkafi Hiroyuki Ogata Nathalie Barouh Benjamin Fouquet Régine Lebrun Michel Pina Frantz Scheirlinckx Pierre Villeneuve Frédéric Carrière 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2009,1791(11):1048-1056
An esterase (CpEst) showing high specific activities on tributyrin and short chain vinyl esters was obtained from Carica papaya latex after an extraction step with zwitterionic detergent and sonication, followed by gel filtration chromatography. Although the protein could not be purified to complete homogeneity due to its presence in high molecular mass aggregates, a major protein band with an apparent molecular mass of 41 kDa was obtained by SDS-PAGE. This material was digested with trypsin and the amino acid sequences of the tryptic peptides were determined by LC/ESI/MS/MS. These sequences were used to identify a partial cDNA (679 bp) from expressed sequence tags (ESTs) of C. papaya. Based upon EST sequences, a full-length gene was identified in the genome of C. papaya, with an open reading frame of 1029 bp encoding a protein of 343 amino acid residues, with a theoretical molecular mass of 38 kDa. From sequence analysis, CpEst was identified as a GDSL-motif carboxylester hydrolase belonging to the SGNH protein family and four potential N-glycosylation sites were identified. The putative catalytic triad was localised (Ser35-Asp307-His310) with the nucleophile serine being part of the GDSL-motif. A 3D-model of CpEst was built from known X-ray structures and sequence alignments and the catalytic triad was found to be exposed at the surface of the molecule, thus confirming the results of CpEst inhibition by tetrahydrolipstatin suggesting a direct accessibility of the inhibitor to the active site. 相似文献
829.
Duvignaud JB Savard C Fromentin R Majeau N Leclerc D Gagné SM 《Biochemical and biophysical research communications》2009,379(1):27-31
It has been reported that cyclosporine A (CsA) aggravates vascular injury in hyperlipidemic patients, but the specific mechanisms are unclear. We explored the hypothesis that CsA may result in complement-mediated endothelial cell lysis induced by down-regulation of decay-accelerating factor (DAF) in hyperlipidemic patients. Human umbilical vein endothelial cells (HUVECs) were treated with CsA or/and oxidized low-density lipoprotein (ox-LDL) before allowing DAF expression. Complement factor C3 cell binding was measured by flow cytometry. CsA exposure led to decreased DAF expression and aggravated cell lysis of the HUVECs pre-incubated with ox-LDL, in a dose-dependent fashion. In in vivo experiments using thoracic aortic endothelium from hyperlipidemic rats, CsA resulted in dose-dependent down-regulation of DAF, and accompanying endothelial damage. These observations provide new evidence that hyperlipidemic patients treated with CsA may have an increased vascular risk, at least in part through complement-mediated EC lysis following down-regulated DAF expression. 相似文献
830.