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Isolation and characterization of rice lesion mimic mutants from a T-DNA tagged population

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Progress in Natural Science:Materials International 2005年第1期 18-24页

作者： LI Shutian 1,2. PEI Zhongyou 1, LUO Lijuan 3. TIAN Yingchuan 1 and HE Chaozu 1* (1. National key laboratory of Plant Genomics, {2. of Microbiology, The chinese academy of sciences, beijing 100080, china 2. graduate school of the chinese academy of sciences, beijing 10003., china 3. College of Agronomy, South china University of Tropical Agriculture, Danzhou 57173., china)

A rice (Oryza sativa L. ssp. japonica cv. Nipponbare) T-DNA tagged population consisting of about 7000 individual lines was generated and screened for rice lesion mimic mutants in the T 1 generation. Ten lines were found to develop spontaneous lesions in the absence of pathogen infection and displayed distinct lesion phenotypes. These mutants were tentatively designated as lm1—lm10 (for lesion mimic), respectively. Lesion formation of lm mutants was developmentally regulated, and all the mutants showed stunted growth and reduced fertility. Genetic analysis demonstrated that all the mutations were recessive, and five partially fertile mutants (lm4—lm8) were derived from different loci. Mimic lesions occurring on the leaves of lm mutants resulted from cell death as revealed by trypan blue staining. Six of them (lm3.lm8) exhibited enhanced resistance to five bacterial blight isolates, indicating their wide-spectrum resistance to this pathogen. These results imply that some lesion mimic mutations of rice might be involved in disease resistance signaling pathways, and that isolation of these mutated genes may be useful for elucidating molecular mechanisms of plant disease resistance. Among the mutants, only one mutant, lm6, was preliminarily shown to cosegregate with the inserted T-DNA in its T 1 generation, making it feasible to isolate the gene responsible for the phenotype of this mutant.

关键词： T-DNA tagging lesion mimic hypersensitive response Xanthomonas oryzae pv. Oryzae Oryza sativa.

Tillage Pedogenesis of Purple Soils in Southwestern china

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Journal of Mountain Science 2009年第2期6卷 205-210页

作者： HE Xiubin BAO Yuhai NAN Hongwei XIONG Donghong WANG Li LIU Yanfeng ZHAO Jingbo institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China graduate school of the{2. Beijing 100049 China Shaanxi Normal University Xi'an 710062 China

Land cultivation and tillage process, and their consequent impacts on soil erosion, have been criticized as the main cause of degradation of land or soil quality. However, purple soils, classified as Regosols in FAO Taxonomy or Entisols in USDA Taxonomy, are formed from purple rocks of the Trias- Cretaceous system, have been developed or at least accelerated the development due to continual tillage operation, especially digging and ridging. The present study took micromorphological investigation on the sedimentary rocks and the soils under different operations of tillage. Results show that the purple rock of Feixiangguan Formation of the Trias system （Tlf） is the easiest to physical weathering and the most fertile soil material enriched in nutrients, and it has been, therefore, mostly cultivated and intensively tilled around the year. It has the fastest soil formation rate. Soil formation rate in the cropland with conventional tillage is higher than that in the forestiand and the grassland. It implies that the artificial brokenness and tillage disturbance play a great role in physical weathering and initiating soil formation processes.

关键词： Tillage impact pedogenesis purple soil micromorphology southwestern china

Algebraic Attack on Filter-Combiner Model keystream Generators

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wuhan University Journal of Natural sciences 2005年第1期10卷 259-262页

作者： WUZhi-ping YEDing-feng MAWei-ju StatekeylaboratoryofInformationSecurity（{2.{3.ofchineseacademyofsciences） Beijing100039China

Algebraic attack was applied to attack Filter-Combintr model keystreamgenerators. We proposed the technique of function composition to improve the model, and the improvedmodel can resist the algebraic attack. A new criterion for designing Filter-Combiner model was alsoproposed: the total length I. of Linear Finite State Machines used in the model should be largeenough and the degree d of Filter-Combiner function should be approximate [L/2..

关键词： algebraic attack Filter-Combiner model stream cipher 'XL' algorithm function composition

Thymic epithelial progenitor cells and thymus regeneration: an update

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Cell Research 2007年第1期17卷 50-55页

作者： L ianjun Zhang~(1,2. Liguang Sun~(1,3. Yong Zhao~1 ~1Transplantation Biology Research Division,State key laboratory of Biomembrane and Membrane Biotechnology,{2. of Zoology,~2.3. University of the chinese academy of sciences,chinese academy of sciences,beijing 100080,china,~3.11} of Public Health,Jilin University,Changchun 13.02.,china TransplantationBiologyResearchDivision StateKeyLaboratoryofBiomembraneandMembraneBiotechnologyInstituteofZoology graduateUniversityofthechinese{2.of{3. ChineseAcademyofSciencesBeijing100080China

The thymus provides the essential microenvironment for T-cell development and *** epithelial cells(TECs),which are composed ofthymic cortical epithelial cells (cTECs) and thymic medullary epithelial cells (mTECs),have been well documented to be critical for these tightly regulated *** has long been controversial whether thecommon progenitor cells of TECs could give rise to both cTECs and *** progress has been made to charac-terize the common TEC progenitor cells in recent *** herein discuss the sole origin paradigm with regard to TECdifferentiation as well as these progenitor cells in thymus regeneration.

关键词： thymic epithelial progenitor cells thymus organogenesis thymus regeneration

On gl■k2.urrent Superalgebra and Twisted Conformal Field Theory

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Communications in Theoretical Physics 2007年第1期 69-77页

作者： DING Xiang-Mao~1 WANG Gui-Dong~(1,2. WANG Shi-Kun~(1,3.1 institute of Applied Mathematics,academy of Mathematics and Systems Science,the{2.,P.O.Box 2.3.,beijing 100080,china2.graduate school of the chinese academy of Scisences,beijing {13.,china3.KLMM,AMSS,CAS,beijing 100080,china

Motivated by the recently discovered hidden symmetry of the type IIB Green-Schwarz superstring oncertain background,the non-semisimple Kac-Moody twisted superalgebra glis investigated by means of thevector coherent state method and boson-fermion *** free field realization of the twisted current superalgebraat general level k is *** corresponding Conformal Field Theory (CFT) has zero central *** the classification theory,this CFT is a nonunitary field theory. After projecting out a U(1) factor and an outerautomorphism operator,we get the free field representation of psl,which is the algebra of glmodulothe Z-outer automorphism,the CFT has central charge -2.

关键词： superalgebra differential operator realization free field realization conformal field theory

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氨酰tRNA合成酶专一性识别的进化

生物化学与生物物理进展 2002年第6期29卷 837-841页

作者：林军黄京飞中国科学院昆明动物研究所中国科学院细胞与分子进化重点实验室中国科学院研究生院北京10003.

氨酰 tRNA合成酶 (AARS)是一类在蛋白质合成过程中起着重要作用的酶 ,它通过与tRNA及其相应氨基酸的专一性识别作用 ,使得基因序列能够被精确地翻译成蛋白质序列 .然而 ,氨酰 tRNA合成酶的这种识别作用既有专一性 ,也具有“兼容性” .... 详细信息

氨酰 tRNA合成酶 (AARS)是一类在蛋白质合成过程中起着重要作用的酶 ,它通过与tRNA及其相应氨基酸的专一性识别作用 ,使得基因序列能够被精确地翻译成蛋白质序列 .然而 ,氨酰 tRNA合成酶的这种识别作用既有专一性 ,也具有“兼容性” .氨酰 tRNA合成酶的这种双重性质不仅与其结构的进化有关 ,而且还与其所处的各类生物的不同进化阶段有关 .AARS似乎经历了一个由“模糊专一性” (多重专一性 )到“精确专一性”(单一专一性 )

关键词：氨酰-tRNA合成酶专一性识别进化结构同源性功能演化

Cloning and Characterization of β-Carotene Ketolase Gene Promoter in Haematococcus pluvialis

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Acta Biochimica et Biophysica Sinica 2005年第4期37卷 270-275页

作者： Chun-Xiao MENG~(1,2. Chang-Ying TENG~1 Peng JIANG~1 Song QIN~1 Cheng-Kui TSENG~1 ~1institute of Oceanology,chinese {2. of sciences.Qingdao 2.6071,china ~2.5} school of the chinese academy of sciences,beijing 10003..china instituteofOceanology ChineseAcademyofSciencesQingdao266071China

The unicellular green alga Haematococcus pluvialis accumulates a highly valuable ketocarotenoid,astaxanthin,under various environmental stresses.β-carotene ketolase (BKT) plays a key role in astaxanthinbiosynthesis in *** this paper,an approximate 700 bp 5'-flanking region of the bkt gene contain-ing a putative promoter was cloned through walking *** results of the sequence analysis showedthat this bkt 5'-flanking region might have cis-acting elements such as sterol regulatory element(SRE-1)-likemotifs,the C-repeat/dehydration responsive element (DRE) and al-3.proximal element (APE)-like *** for typical TATA and CCAAT *** results of the β-galactosidase assay and the transientexpression of lacZ driven by a series of sequential deletions revealed that a minimal promoter-like regionmight exist from-63. to-408 bp,and the highest promoter activity was observed to span the positionsfrom-63. to-3.8 *** results of the site-directed mutagenesis of a C-repeat/DRE and two APE-likemotifs in a promoter-like region(-63. to -3.8 bp)suggested that two APE-like motifs might be essential fortranscriptional control of the bkt gene.

关键词： Haematococcus pluvialis astaxanthin β-carotene ketolase gene (bkt) cis-acting element promoter

Spatial Prediction of Heavy Metal Pollution for Soils in Peri-Urban beijing, china Based on Fuzzy Set Theory

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Pedosphere 2006年第5期16卷 545-554页

作者： TAN Man-Zhi XU Fang-Ming CHEN Jie ZHANG Xue-Lei CHEN Jing-Zhong State key laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） graduate school of the{2. Beijing 100039 Chengdu University of Technology Chengdu 610059 （China） Nanjing Station of Soil and Fertilizer Nanjing 210036 （China）

Fuzzy classification combined with spatial prediction was used to assess the state of soil pollution in the peri-urban beijing area. Total concentrations of As, Cr, Cd, Hg, and Pb were determined in 2.0 topsoil samples （0-2. cm） collected using a grid design in a study area of 2.600 kin2. Heavy metal concentrations were grouped into three classes according to the optimum number of classes and fuzziness exponent using the fuzzy comean （FCM） algorithm. Membership values were interpolated using ordinary kriging. The polluted soils of the study area induced by the measured heavy metals were concentrated in the northwest corner and eastern part, especially the southeastern part close to the urban zone, whereas the soils free of pollution were mainly distributed in the southwestern part. The soils with potential risk of heavy metal pollution were located in isolated spots mainly in the northern part and southeastern corner of the study region. The FCM algorithm combined with geostatistical techniques, as compared to conventional single geostatistical kriging methods, could produce a prediction with a quantitative uncertainty evaluation and higher reliability. Successful prediction of soil pollution achieved with FCM algorithm in this study indicated that fuzzy set theory had great potential for use in other areas of soil science.

关键词： continuous classification fuzzy c-means heavy metal soil pollution spatial prediction

Formation of the Yazi Spring Stream and its significance on tectonics-climate on the northern slope of Kunlun Mountains

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Science Bulletin 2005年第18期 97-102页

作者： CHANG Hong1,2. ZHANG Peizhen3. AN Zhisheng1, WANG Xulong1, QIANG Xiaoke1 & FU Chaofeng1 1. State key laboratory of Loess and Quaternary Geology, {2. of Earth Environment, chinese academy of sciences, Xi’an 710075, china 2. graduate school of chinese academy of sciences, beijing 10003., china 3. State key laboratory of Seismic {12.s, china Earthquake Ad-ministration, beijing 10002., china

The sequences of fluvial terraces in the Yazi Spring Stream are signs of the stepwise uplift of the Kunlun Mountains in the northern part of the Tibetan Plateau since the Late Pleistocene. Geomorphic and sedimentary features of the terraces reveal that they have resulted from the phased tectonic uplift and the consequent river incision in the northern plateau. Using the method of Single-aliquot Regenerative-dose (SAR) Protocol and Radiocarbon 14C dating, the deposit ages of three-grade terraces were ob- tained, which are 57.5, 12.8 and 5.7 kaBP, respectively. The features and ages of terraces reveal that the incision rate of the stream accelerated at the beginning of the Holocene. The incision rate changed suddenly at 12.8 KaBP, from 0.43.0.07 mm/a to 1.59±0.55 mm/a. This implicates that uplift of the Kunlun Mountains is intensive at the first onset of the Holo- cene, corresponding to the obvious change of slip-rate on the Altyn Tagh Fault. But its uplift rate is much lower than that of the latter, which suggests that growth of the northern mar- gin of the Tibetan Plateau is stronger than its interior.

关键词： Tibetan Plateau Kunlun Mountains terrace optically stimulated luminescence tectonic uplift.