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Disruption of phytoene desaturase gene results in albino and dwarf phenotypes in Arabidopsis by impairing chlorophyll, carotenoid, and gibberellin biosynthesis

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Cell research 2007年第5期17卷 471-482页

作者： Genji Qin1 Hongya Gu1,2 Ligeng Ma1,3 Yiben Peng1 Xing Wang Deng1,3 Zhangliang Chen1 Li-Jia Qu1,2 1 Peking-Yale Joint center for Plant Molecular Genetics and Agrobiotechnology, National Laboratory for Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking university, Beijing 100871, china 2 The National Plant Gene research center (Beijing), Beijing 100101, china 3 Department of Molecular, cellular, and Developmental Biology, Yale university, New Haven Connecticut 62520-8104, USA Peking-Yale Joint center for Plant Molecular Genetics and Agrobiotechnology National Laboratory for Protein Engineering and Plant Genetic Engineering College of Life Sciences Peking University Beijing China The National Plant Gene research center (Beijing) Beijing China Department of Molecular Cellular and Developmental Biology Yale University New Haven Connecticut USA

Carotenoids play an important role in many physiological processes in plants and the phytoene desaturase gene （PDS3）encodes one of the important enzymes in the carotenoid biosynthesis pathway. Here we report the identification andanalysis of a T-DNA insertion mutant of PDS3 gene. functional complementation confirmed that both the albino anddwarf phenotypes of the pds3 mutant resulted from functional disruption of the PDS3 gene. Chloroplast development wasarrested at the proplastid stage in the pds3 mutant. Further analysis showed that high level of phytoene was accumulatedin the pds3 mutant. Addition of exogenous GA3could partially rescue the dwarf phenotype, suggesting that the dwarfphenotype of the pds3 mutant might be due to GA deficiency. Microarray and RT-PCR analysis showed that disruptingPDS3 gene resulted in gene expression changes involved in at least 20 metabolic pathways, including the inhibition ofmany genes in carotenoid, chlorophyll, and GA biosynthesis pathways. Our data suggest that the accumulated phytoenein the pds3 mutant might play an important role in certain negative feedbacks to affect gene expression of diverse cel-lular pathways.

关键词： Arabidopsis thaliana phytoene desaturase albino dwarf microarray analysis

Prediction method for October 2003 solar storm

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Science china(Technological Sciences) 2006年第5期49卷 629-640页

作者： XIE Yanqiong1, 2, 3, WEI Fengsi1, FENG Xueshang1 & ZHONG Dingkun1, 2 1. State Key Laboratory of Space Weather, center for Space Science and Applied research, Chinese Academy of Sciences, Beijing 100080, china 2. Graduate School, Chinese Academy of Sciences, Beijing 100039, china 3. Institute of Meteorology, PLA university of Science and Technology, Nanjing 211101, china State Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China Graduate School Chinese Academy of Sciences Beijing China Institute of Meteorology PLA University of Science and Technology Nanjing China

Aiming at two intense shock events on October 28 and 29, 2003, this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the Earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely high temperature, the strong magnetic field, and the high speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1% and 3.1%, re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

CJZ3,a Iomerizine derivative,modulates P-glycoprotein function in rat brain microvessel endothelial cells

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Acta Pharmacologica Sinica 2006年第4期27卷 414-418页

作者： Bian-sheng JI~2 Ling HE~3 Xiao-qu LI~4 Guo-qing LIU~(3,5) ~2Institute of Pharmacy,Henan university,Kaifeng 475001.china ~3Department of Pharmacology,china Pharmaccutical university.Nanjing 210009,china:~4School of Life Sciences,Beijing Normal university,Beijing 100875,china Institute of Pharmacy Henan University Kaifeng China Department of Pharmacology China Pharmaceutical University Nanjing China School of Life Sciences Beijing Normal University Beijing China

Aim:To investigate the modulatory effect of CJZ3,a lomerizine derivative,onP-glycoprotein(P-gp)function in rat brain microvessel endothelial cells(RBMEC).Methods:RBMEC were isolated and cultured in Dulbecco's modified Eagle's me-dium/F12(1:1)medium,and the amount of intracellular rhodamine 123(Rh 123)wasdetermined using a fluorescence spectrophotometer to evaluate the modulatoryeffect of CJZ3 on P-gp ***:The accumulation of Rh 123 was poten-tiated in a concentration-dependent manner after incubation with CJZ3 for RBMEC,but not for human umbilical vein endothelial cells(HUVEC).CJZ3 caused theaccumulation of intracellular Rh123 in a time-dependent manner and significantlydecreased the effiux of Rh 123 from the *** inhibitory effect of CJZ3 on P-gpfunction was reversible and remained for 120 min after CJZ3(2.5 μmol/L)wasremoved from the ***:CJZ3 has a potent in vitro effect on theinhibition of P-gp function.

关键词： CJZ3 P-glycoprotein blood-brain barrier

miRNAs modulate the drug response of tumor cells

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Science china(Life Sciences) 2009年第9期52卷 797-801页

作者： WU XueMei1,3 & XIAO HuaSheng1,2 1 center of functional Genomics,Key Laboratory of System Biology,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,china 2 National Engineering center for Biochip at Shanghai,Shanghai 201203,china 3 Graduate university of Chinese Academy of Sciences,Shanghai 200031,china center of functional Genomics Key Laboratory of System Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China Graduate university of Chinese Academy of Sciences Shanghai China National Engineering center for Biochip at Shanghai Shanghai China

Chemotherapy is one of the major treatments of malignant carcinomas. However,its efficiency is affected by both intrinsic and acquired resistance to anticancer drugs. The cellular mechanisms of drug resistance include the overexpression of energy-dependent transporters that eject anticancer drugs from cells such as p-glycoprotein and multidrug resistance related protein (MRP),the mutation of drug targets,the activation of DNA repair pathways,the defects in cellular death pathways and so on. The genetic and epigenetic changes of these genes can lead to cancer drug resistance. Among these mechanisms,microRNAs (miRNAs) which are critical and essential for many important processes such as development,differentiation,and even carcinogenesis have been reported to regulate the chemosen-sitivity of tumor cells. In this paper we briefly review the relationship between miRNA and cancer drug resistance.

关键词： cancer drug resistance miRNAs

Real-time reliability prediction for dynamic systems with both deteriorating and unreliable components

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Science in china(Series F) 2009年第11期52卷 2234-2246页

作者： XU ZhengGuo1,2, JI YinDong2,3 & ZHOU DongHua1,2? 1 Department of Automation, Tsinghua university, Beijing 100084, china 2 Tsinghua National Laboratory for Information Science and Technology, Tsinghua university, Beijing 100084, china 3 research Institute of Information Technology (RIIT), Tsinghua university, Beijing 100084, china Department of Automation Tsinghua University Beijing China Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing China research Institute of Information Technology (RIIT) Tsinghua University Beijing China

As an important technology for predictive maintenance, failure prognosis has attracted more and more attentions in recent years. Real-time reliability prediction is one effective solution to failure prognosis. Considering a dynamic system that is composed of normal, deteriorating and unreliable components, this paper proposes an integrated approach to perform real-time reliability prediction for such a class of systems. For a deteriorating component, the degradation is modeled by a time-varying fault process which is a linear or approximately linear function of time. The behavior of an unreliable component is described by a random variable which has two possible values corresponding to the operating and malfunction conditions of this component. The whole proposed approach contains three algorithms. A modified interacting multiple model particle filter is adopted to estimate the dynamic system＇s state variables and the unmeasurable time-varying fault. An exponential smoothing algorithm named the Holt＇s method is used to predict the fault process. In the end, the system＇s reliability is predicted in real time by use of the Monte Carlo strategy. The proposed approach can effectively predict the impending failure of a dynamic system, which is verified by computer simulations based on a three-vessel water tank system.

关键词： reliability failure prognostics dynamic systems fault prediction particle filtering interacting multiple model exponential smoothing,predictive maintenance

Identification and characterization of two novel box H/ACA snoRNAs from Schizosaccharomyces pombe

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Progress in Natural Science:Materials International 2005年第6期15卷 507-514页

作者： LI Siguang, ZHOU Hui, ZHANG Peng, LUO Yuping and QU Lianghu*(Key Laboratory of Gene Engineering of the Ministry of Education, Biotechnology research center, Zhongshan university, Guangzhou 510275, china) Key Lab. of Gene Eng. of the Min. of Edu. Biotechnology Research Center Zhongshan University Guangzhou 510275 China

Through constructing a specialized cDNA library based on small RNAs isolated from partial purified nuclei of Schizosaccharomyces pombe, two novel noncoding RNAs, termed Sp15-70 and Sp18-61, have been identified. Bioinformatics analysis reveals that both the novel RNAs possess a typical secondary structure of box H/ACA snoRNA and antisense elements to rRNAs. According to the relationship between the structure and function of box H/ACA snoRNA, Sp15-70 was predicted to direct pseudouridylation in 25S rRNA at U2401 and U2298; Sp18-61 was predicted to direct pseudouridylation in 18S rRNA at U208 and 25S rRNA at U2341. The four predicted pseudouridylation sites were all verified experimentally by the CMC-primer extension analysis. Both Sp15-70 and Sp18-61 were encoded by single copies which were located in the intergenic regions between the CDS of two protein-coding genes on chromosome Ⅰ and Ⅲ of S. pombe, respectively. Putative TATA-like elements can be found upstream from the 5′ end of these snoRNA genes, suggesting that they could be transcribed from their own promoters. Comparison of the two snoRNAs and their functional homologues in diverse organisms reveals that extensive recombinations among different snoRNAs have occurred during the evolution from their primitive progenitors.

关键词： box H/ACA snoRNA RNA pseudouridylation gene evolution Schizosaccharomyces pombe.

Relationship and its instability of ENSO--Chinese variations in droughts and wet spells

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Science china Earth Sciences 2007年第1期50卷 145-152页

作者： SU MingFeng1,2 & WANG HuiJun1 1 Nansen-Zhu International research center, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, china 2 Graduate university of Chinese Academy of Sciences, Beijing 100039, china Nansen-Zhu International research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate university of Chinese Academy of Sciences Beijing China

Monthly data of Self-Calibrated Palmer Drought Severity Index (PDSI) from 1951 to 2000 are calculated using historical precipitation and temperature data for Chinese 160 stations. Temporal and spatial pat-terns of the first empirical orthogonal function (EOF) of the PDSI reveals a fairly linear trend resulting from trends in precipitation and surface temperature, which is similar to the linear PDSI trend during 1951―2000 calculated using all monthly data. The EOF analysis also reveals that the leading mode correlates significantly with ENSO events in time and space. The ENSO EOF shows that during the typical warm phase of ENSO, surface conditions are drier in most regions of china, especially North china, but wetter than normal in the southern regions of Changjiang River, and Northwest china. During the typical cold phase of ENSO, these anomalies reverse sign. From 1951 to 2000, there are large multi-year to decadal variations in droughts and wet spells over china, which are all closely related to strong El Nio events. In other words, when one strong El Nio event happens, there is a possible big variability in droughts and wet spells over china on the multi-year or decadal scale. Studies also sug-gest that during the last 2―3 decades climate changes over china, especially North china's drying and northwest china's wetting, are closely related to the shift in ENSO towards warmer events and global warming since the late 1970s. The instability of the relationship is also studied. It is revealed that there is a good correlation between ENSO and Chinese variations in droughts and wet spells in the 3―8-year band, but the correlation between ENSO and Chinese variations in droughts and wet spells is instable. Studies suggest that there are decadal changes in the correlation: the wavelet coherency between ENSO and Chinese variations in droughts and wet spells is high during 1951―1962 and 1976―1991, but low during 1963―1975 and 1992―2000.

关键词： PDSI variations droughts and wet Spells ENSO instability.

Differential Hydrological Grey Model (DHGM) with self-memory function and its application to flood forecasting

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Science china(Technological Sciences) 2009年第4期52卷 1039-1049页

作者： CHEN XiangDong1, XIA Jun1,2 & XU Qian3 1 Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources research, Chinese Academy of Sciences, Beijing 100101, china 2 State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan university, Wuhan 430072, china 3 School of Hydrology and Water Resources, Hohai university, Nanjing 210098, china Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan China School of Hydrology and Water Resources Hohai University Nanjing China

This paper addresses a problem of flood forecasting with the self-memory function. Considering flood forecasting’s uncertainty and updating demand, a hybrid hydrological model, namely Differential Hy- drological Grey Model with self-memory function (DHGM-SM), is developed. The model has two fold features. One is to establish a self-memorization equation linked with DHGM, that could extract useful information from past data series and realize updating of hydrological dynamic process. The other is that this model has higher efficiency relative to original hydrological model without self-memory func- tion. This approach was applied to river flow forecasting of two representative basins in Tunxi of South china and Daqinggou of North china. It is shown that this hybrid method has satisfactory forecasting accuracy by examination of both calibration and validation.

关键词： differential grey model the self-memorization principle real-time forecasting faded-memory recursive least square method

Perspectives on the origin of microfilaments, microtubules, the relevant chaperonin system and cytoskeletal motors- a commentary on the spiro chaete origin of flagella

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Cell research 2003年第4期13卷 219-227页

作者： JING YAN LI, CHUAN FEN WULaboratory of cellular and Molecular Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, china Department of Molecular Genetics, M. D. Anderson Cancer center, The university of Texas, Houston, TX 77030, USA Laboratory of cellular and Molecular Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming China

The origin of cytoskeleton and the origin of relevant intracellular transportation system are big problems for understanding the emergence of eukaryotic cells. The present article summarized relevant information of evidences and molecular traces on the origin of actin, tubulin, the chaperonin system for folding them, myosins, kinesins, axonemal dyneins and cytoplasmic dyneins. On this basis the authors proposed a series of works, which should be done in the future, and indicated the ways for reaching the targets. These targets are mainly: 1) the reconstruction of evolutionary path from MreB protein of archaeal ancestor of eukaryotic cells to typical actin; 2) the finding of the MreB or MreB-related proteins in crenarchaea and using them to examine J. A. Lake’s hypothesis on the origin of eukaryote from 'eocytes' (crenarchaea); 3) the examinations of the existence and distribution of cytoskeleton made of MreB-related protein within coccoid archaea, especially in amoeboid archaeon Thermoplasm acidophilum;

关键词： origin actin tubulin motor proteins Bagella and cilia spirochaete hypothesis.