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Advances in G-protein coupled receptor research and related bioinformatics study

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Chinese Science Bulletin 2003年第6期48卷 511-516页

作者： YINYanbin LUOJingchu 等 collegeoflifesciences NationalLaboratoryofPlantGeneticEngineeringandProteinEngineeringCenterofBioinformaticsPekingUniversityBeijing100871China collegeoflifesciences NationalLaboratoryofPlantGeneti

G-protein coupled receptor (GPCR) is one of the most important protein families for drug target. GPCR agonists and antagonists occupy approximately one third of the world small molecule drug market. Much effort has been invested in GPCR study by both academic institutions and pharmaceutical industries. With seven-transmembrane do-mains, GPCR plays significant roles in intercellular signal transduction and is involved in a variety of biological path-ways. With the availability of sequence data of human and other mammalian genomes, as well as their expressed se-quence tag (EST) data, the bioinformatics and genomics approaches can be applied to identifying novel GPCR in the post genomic era. Deorphanizing GPCR or matching ligands with GPCR greatly facilitates target validation process and automatically provides a possible compound screening assay. Similarly, bioinformatics data mining approach could also be applied to the identification of GPCR peptide or protein ligands. Here we give a general review of recent advances in the study of GPCR structure, function, as well as GPCR and ligand identification with the emphasis on the bioinformatics database mining of GPCR and their peptide or protein ligands.

关键词： G蛋白耦合受体生物信息学研究跨膜蛋白信号转导配体孤儿受体药物开发

Cytotoxicity of HIV-gp41 segments expressed in E.coli

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Chinese Science Bulletin 2004年第7期49卷 668-671页

作者： YUANYuhua BIChanghao LIJu WANGXueqian GENGYunqi CHENQimin collegeoflifesciences NankaiUniversityTianjin300071China

The failed attempt to express HIV-gp41 in E. coli led to the investigation of HIV-gp41 segments, which is responsible for the toxicity to E. coli cells. A series of dele-tion mutants containing different regions of gp41 gene were constructed and expressed in E. coli BL21(DE3) strain. After IPTG induction, the high mortality of host bacteria was ob-served in host bacteria carrying the deletion mutants of gp41 gene except for those transformed with pET-HN2; coordi-nately, the mRNA transcripts of the gp41 was rapidly de-creased; and the release of [3H]uridine increased upon in-duction. All these data suggested that GP41 protein has a cytotoxic effect on E. coli, and it is the cytotoxicity of the gp41 gene product that contributes to the high mortality when expressed in E. coli.

关键词： HIV-gp41 基因表达细胞毒素 E.coli 宿主细菌横跨膜蛋白

Seminal, adventitious and lateral root growth and physiological responses in rice to upland conditions

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Journal of Zhejiang University Science 2003年第4期4卷 469-473页

作者：杨玲郑炳松毛传澡易可可吴运荣吴平陶勤南 collegeoflifesciences ZhefiangUniversityHangzhou310029China

Understanding the growth and physiological responses of rice to upland conditions would be help-ful for designing treatments to improve the tolerance of rice under a rainfed system. The objective of this studywas to investigate the initiation, elongation and membrane stability of seminal, lateral and adventitious roots of upland rice after 9-d upland condition treatment. Compared with control roots under waterlogged conditions,upland water deficiency conditions favor seminal and lateral root growth over adventitious root growth by accel-erating seminal root elongation, promoting lateral root initiation and elongation, and reducing the elongation and number of adventitious roots. Enhanced total root number and length resulted in increase of total root dryweight and thereby increasing the mot-to-shoot ratio. Organic compound leakage from seminal root tips and ad-ventitious roots increased progressively to some extent with upland culture duration, while significant increasesin seminal root tips were the consequence of loss of membrane integrity caused by the upland-condition en-haneed growth.

关键词：水稻山地种子根侧根不定根生长发育生理反应

Analysis of Seed-expressed Sequence Tags in Triticum aestivum

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Acta Botanica Sinica 2004年第3期46卷 363-370页

作者： LIJia-Rui WANGFang ZHAOXiang-Yu DONGYu-Xiu ZHANGLi-Yuan ZHANGXian-Sheng collegeoflifesciences ShandongAgriculturalUniversityTaian271018China

To isolate seed-expressed sequences, a cDNA library was constructed using wheat ( Triticumaest/vum L) seed tissues at 12 d after pollination. Plasmid DNAs of 10 000 clones randomly picked out fromthe library were prepared. The preparation of high density filters were made with the Biomek 2000 HDRTsystem, and then hybridized separately with three probes prepared by reverse transcription of RNA ofunpollinated ovary, embryo and endosperm. Based on the hybridization results, 800 clones expressed inembryo and/or endosperm were chosen for further analysis of expressed sequence tags (ESTs). Finally,216 different genes were identified preliminarily. Of them, 24 (11.5%) were considered identical to knownwheat genes, 122 (56%) were identified as putative new plant genes which may be involved in seed storageproteins, biochemical metabolisms, development, and other biological processes of seeds, while 70 (32.5%)sequence identities could not be determined.

关键词：小麦种子 cDNA阵列表达序列标签基因生物学

Comparative mapping of QTLs for AI tolerance in rice and identification of positional Al-induced genes

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浙江大学学报：自然科学英文版 2004年第6期5卷 634-643页

作者：毛传澡杨玲郑炳松吴运荣刘非燕易可可吴平 StateKeyLaboratoryofPlantPhysiologyandBiochemistry CollegeofLifeSciencesZhejiangUniversityHangzhou310029China

Aluminum (A1) toxicity is the major factor limiting crop productivity in acid soils. In this study, a recombinant inbreed line (RIL) population derived from a cross between an A1 sensitive lowland indica rice variety IR1552 and an A1 tolerant upland japonica rice variety Azucena, was used for mapping quantitative trait loci (QTLs) for A1 tolerance. Three QTLs for relative root length (RRL) were detected on chromosome 1,9, 12, respectively, and 1 QTL for root length under A1 stress is identical on chromosome 1 after one week and two weeks stress. Comparison of QTLs on chromosome 1 from different studies indicated an identical interval between C86 and RZ801 with gene(s) for A1 tolerance. This interval provides an important start point for isolating genes responsible for A1 tolerance and understanding the genetic nature of Al tolerance in rice. Four A1 induced ESTs located in this interval were screened by reverse Northern analysis and confirmed by Northern analysis. They would be candidate genes for the QTL.

关键词：水稻铝耐性定量特征轨迹表达序列标签基因产量相关根系长度

Secretory Structures and Their Relationship to Accumulation of Camptothecin in Camptotheca acuminata （Nyssaceae）

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Acta Botanica Sinica 2004年第10期46卷 1242-1248页

作者： LIUWen-Zhe collegeoflifesciences NorthwestUniversityXi＇an710069China

Camptotheca acuminata Decne. (Nyssaceae) is a major source of the anticancer camptothecin (CPT). It is important to understand how CPT accumulates in C.acuminata in order to improve CPT production strategies. The aim of this study was to anatomically and morphologically characterize the secretory structure in leaves and stems of C.acuminata and determine their relationship to accumulation of OPT. Secretory canals and glandular trichomes were found in young stems and young leaves. Secretory canals consisted of a sub-epidermal canal delimited by one to two layers of cells. Glandular trichomes were unicellular. Fluorescence microscopy and OPT analysis showed that OPT was primarily accumulated in secretory canals and glandular trichomes of leaves and stems.

关键词：分泌结构累积喜树碱荧光显微镜植物

Change of Nitric Oxide and NADPH-diaphorase During the Generation and the Development of Adventitious Roots in Mung Bean Hypocotyl Cuttings

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Acta Botanica Sinica 2004年第9期46卷 1049-1055页

作者： SHEXiao-Ping HUANGAi-Xia collegeoflifesciences ShannxiNormalUniversityXi＇an710062China

Effects of nitric oxide (NO) donor sodium nitroprusside (SNP), NO specific scavenger c-PTIO and nitric oxide synthase (NOS) inhibitor L-NAME on the rooting of mung bean ( Vigna radiata L.) hypocotyl cuttings were studied. The spatio-temporal changes of NO and NADPH-diaphorase in the basal part of cutting were also detected during the adventitious rooting process. The results showed that SNP significantly enhanced the adventitious rooting in the range of concentrations tested. NADPH-diaphorase activity (commonly employed as a marker for NOS) and the fluorescence of NO were respectively observed in the zone between the vascular bundles of the basal part of cuttings at 24h and 36h after cutting. The root primordium became discernible at 48h after cutting in the same region, and became more elongate at 60h. NADPH-diaphorase activity and NO fluorescence gradually increased during 48-60h and mainly distributed in root meristem. L-NAME treatment delayed adventitious root emergency and significantly reduced the NADPH-diaphorase staining and the fluorescence of NO. The specific NO scavenger, c-PTIO, also suppressed the fluorescence and inhibited the formation of adventitious roots. These results suggest that endogenous NO appears to play a key role in the generation and development of adventitious roots, and the production of NO in this process may be catalyzed by NOS-like enzyme.

关键词：心肌黄酶不定根绿豆胚轴一氧化氮生长发育

Characteristics of photosynthesis in rice plants transformed with an antisense Rubisco activase gene

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Journal of Zhejiang University Science 2004年第8期5卷 897-899页

作者：金松恒蒋德安李雪芹孙骏威 StateKeyLabofPlantPhysiologyandBiochemistry CollegeofLifeSciencesZhejiangUniversityHangzhou310029China

Transgenic rice plants with an antisense gene inserted via Agrobacterium tumefaciens were used to explore the impact of the reduction of Rubisco activase (RCA) on Rubisco and photosynthesis. In this study, transformants containing 15% to 35% wild type Rubisco activase were selected, which could survive in ambient CO2 concentration but grew slowly compared with wild type controls. Gas exchange measurements indicated that the rate of photosynthesis decreased sig-nificantly, while stomatal conductance and transpiration rate did not change; and that the intercellular CO2 concentration even increased. Rubisco determination showed that these plants had approximately twice as much Rubisco as the wild types,although they showed 70% lower rate of photosynthesis, whichRubsico activase and/or the reduction in carbamylation.was likely an acclimation response to the reduction in Rubsico activase and/or the reduction in carbamylation.

关键词：光合作用转基因水稻抗致敏Rubisco活性基因气体交换测量

Characteristics of Gas Exchange, Chlorophyll Fluorescence and Expression of Key Enzymes in Photosynthesis During Leaf Senescence in Rice Plants

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Journal of Integrative Plant Biology 2005年第5期47卷 560-566页

作者： Xiao-YanWENG Hong-XiaXU De-AnJIANG NationalLaboratoryofPlantPhysiologyandBiochemistry CollegeofLifeSciencesZhejiangUniversityHangzhou310029China

Abstract: Gas exchange, chlorophyll (Chl) fluorescence, photosynthetic pigments, and the expression of Rubisco and Rubisco activase in flag leaves of rice (Oryza sativa L.) from the heading to mature grain stage were investigated. The results showed that the photosynthetic capacity declined after full expansion of flag leaves. The decline of photosynthetic rate (Pn) in two cultivars during natural senescence was accompanied by a decrease in Chl content, as well as in the Rubisco and Rubisco activase contents. The Rubisco and Rubisco activase contents in Zhenong 966 decreased faster than that in Zhenong 952. The Pn diminished without a decrease in intercellular CO2 concentration during the early senescence of flag leaves, indicating that lower photosynthetic capacity is not caused by stomatal limitation but by reduced carboxylation efficiency. During the senescence of flag leaves, the correlation between the change in photosynthetic capacity and the variation in the abundance of Rubisco and Rubisco activase suggested that the decline in Pn of flag leaves could be attributed to the lower level of rbcS and rca transcripts. The PSII and the electron transport rate appeared in the same rate as Pn. However, excitation pressure (1-qP) showed a different pattern and there was an inverse linear correlation between increased excitation pressure and the reduced Rubisco. Therefore, it is likely that the increased excitation pressure resulted from saturation of the electron transport chain, owing to a limitation of the reductant used by the Calvin cycle; in addition, the change in excitation pressure could further mediate the expression of the rbcS and rca genes, resulting in a fast reduction in Rubisco content.

关键词： chlorophyll fluorescence leaf senescence photosynthesis rice (Oryza sativa L.) Rubisco Rubisco activase