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Sub1A is an ethylene-response-factor-like gene that confers submergence tolerance to rice 总被引:10,自引:0,他引:10
Xu K Xu X Fukao T Canlas P Maghirang-Rodriguez R Heuer S Ismail AM Bailey-Serres J Ronald PC Mackill DJ 《Nature》2006,442(7103):705-708
Most Oryza sativa cultivars die within a week of complete submergence--a major constraint to rice production in south and southeast Asia that causes annual losses of over US 1 billion dollars and affects disproportionately the poorest farmers in the world. A few cultivars, such as the O. sativa ssp. indica cultivar FR13A, are highly tolerant and survive up to two weeks of complete submergence owing to a major quantitative trait locus designated Submergence 1 (Sub1) near the centromere of chromosome 9 (refs 3, 4, 5-6). Here we describe the identification of a cluster of three genes at the Sub1 locus, encoding putative ethylene response factors. Two of these genes, Sub1B and Sub1C, are invariably present in the Sub1 region of all rice accessions analysed. In contrast, the presence of Sub1A is variable. A survey identified two alleles within those indica varieties that possess this gene: a tolerance-specific allele named Sub1A-1 and an intolerance-specific allele named Sub1A-2. Overexpression of Sub1A-1 in a submergence-intolerant O. sativa ssp. japonica conferred enhanced tolerance to the plants, downregulation of Sub1C and upregulation of Alcohol dehydrogenase 1 (Adh1), indicating that Sub1A-1 is a primary determinant of submergence tolerance. The FR13A Sub1 locus was introgressed into a widely grown Asian rice cultivar using marker-assisted selection. The new variety maintains the high yield and other agronomic properties of the recurrent parent and is tolerant to submergence. Cultivation of this variety is expected to provide protection against damaging floods and increase crop security for farmers. 相似文献
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1 Results Stoichimetric quantities of lithium acetate,nickel acetate and ammonium dihydrogen phosphate were mixed with ethanol and stirred with heating until complete dissolution.A solution of 1 g chitosan in 1% acetic acid was then poured into the heated and stirred solution until all solvents have evaporated.The precursor was then sintered at 500,600,700,800,900 and 1 000 ℃ for 3 hours.X-ray diffraction results showed that single phase LiNiPO4 was obtained at sintering temperatures above 600 ℃.TEM res... 相似文献
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Summary Gonadectomy reversed the susceptibility response of male and female Swiss mice toAncylostoma caninum infection. Orchiectomy decreased the survival of filariform larvae (p>0.001 to <0.25), whereas ovariectomy increased it significantly (p>0.001 to <0.01).We wish to acknowledge our gratitude to the late Professor H. Swarup for valuable suggestions, to Professor G.N. Johri for laboratory facilities, and to the University Grants Commission, New Delhi, for financial support in the form of a Junior Research Fellowship to I. B. 相似文献
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Exogenous and endogenous glycolipid antigens activate NKT cells during microbial infections 总被引:1,自引:0,他引:1
Mattner J Debord KL Ismail N Goff RD Cantu C Zhou D Saint-Mezard P Wang V Gao Y Yin N Hoebe K Schneewind O Walker D Beutler B Teyton L Savage PB Bendelac A 《Nature》2005,434(7032):525-529
CD1d-restricted natural killer T (NKT) cells are innate-like lymphocytes that express a conserved T-cell receptor and contribute to host defence against various microbial pathogens. However, their target lipid antigens have remained elusive. Here we report evidence for microbial, antigen-specific activation of NKT cells against Gram-negative, lipopolysaccharide (LPS)-negative alpha-Proteobacteria such as Ehrlichia muris and Sphingomonas capsulata. We have identified glycosylceramides from the cell wall of Sphingomonas that serve as direct targets for mouse and human NKT cells, controlling both septic shock reaction and bacterial clearance in infected mice. In contrast, Gram-negative, LPS-positive Salmonella typhimurium activates NKT cells through the recognition of an endogenous lysosomal glycosphingolipid, iGb3, presented by LPS-activated dendritic cells. These findings identify two novel antigenic targets of NKT cells in antimicrobial defence, and show that glycosylceramides are an alternative to LPS for innate recognition of the Gram-negative, LPS-negative bacterial cell wall. 相似文献
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沙塔尔·司马义 《太原师范学院学报(自然科学版)》2011,10(4):133-137
土壤属性中酸碱性最为影响到土壤产力、养分利用率、植物的分布等.通过检验鄯善县绿洲土壤酸碱性与主要农作物产量做初步对比研究.土壤实验数据分析显示:1)土壤呈碱性,不同剖面0~10cm<10~30cm<30~50cm的碱度依次增大.2)需要大量施用有机肥的同时,要用酸性肥料并分次、多施、深施方法.土壤性质、作物的营养特性与合理施肥相结合. 相似文献
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Zusammenfassung Die als Alexandrin beschriebene Substanz, die als Bestandteil vonCentaurea alexandrina isoliert worden ist, wurde als -sitosterol--d-glukosid identifiziert. 相似文献
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