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1.
抗水稻条纹叶枯病毒核酶的设计,克隆及体外活性测定   总被引:10,自引:0,他引:10  
为探索控制水稻条纹叶枯病毒(Ricestripevirus,RSV)设计合成了特异切割该病毒RNA保守区及编码病害特异性蛋白(DiseaseSpecificProtein,DSP)基因的核酶,核酶基因的长度均为40个碱基,用化学合成方法合成其正链及与其3'-末端互补的15个碱基引物,用TagDNA多聚酶合成其互补链。双链DNA直接插入克隆载体PGEM3zf(+)的Smal位点。序列测定表明,克隆得到的核酶序列与设计的核酶序列完全一致。经SP6RNA多聚酶体外转录得到核酶RNA。当核酶RNA与以同样方法转录得到的靶基因RNA混合反应,可得到预期结果相同的切割片段,表明两种核酶在体外均具有特异性切割活性。  相似文献   

2.
小麦根质膜H^+—ATPase的部分纯化   总被引:2,自引:0,他引:2  
以小麦(TriticumaestivumL.)根为材料,采用不连续蔗糖密度梯度离心法制备高纯度质膜微囊。质膜经TritonX100和KCl处理后,再用Zwitergent314增溶H+ATPase,最后用硫酸铵沉淀得到部分纯化的质膜H+ATPase。SDSPAGE结果表明,经过上述步骤纯化,分子量为94kD的膜蛋白组分得到富集;与质膜相比,其含量提高15.7倍。部分纯化的质膜H+ATPase可以水解ATP,受K+刺激,并被N,N′dicyclohexylcarbodimide(DCCD)抑制;ATP水解活力被Na3VO4抑制95%,但不被NaN3、NaNO3和Na2MoO4抑制。  相似文献   

3.
对普通小麦(TriticumaestivumL.)基因组(AABBDD)最可能的供体-T.uratrtuThum.(AA)、T.monoccumvar.boeoticum(Boiss.)MK(AA)、AegilopsspeltoidesTausch.和Ae.tauschii(Coss.(DD)的核糖体RNA基因ITS区进行了PCR扩增和克隆,并测定了ITS1和ITS2的DNA序列,讨论和纠正了前人  相似文献   

4.
从印度木薯花叶病毒(ICMV)侵染的植物中纯化特异的核酸,经RNAase,DNAasc,Nucle-aseSl,ExonucleaseⅢ和EcoRI酶切,Southern和Dotblots杂交证实,在感病的植株中,存在两种形式的病毒核酸:环状双链DNA和环状单链DNA,后者可能是病毒DNA的(-)链,环状双链DNA经限制性内切酶作用可得2.7kb的线性双链DNA纯化的病毒核酸含DNA1和DNA2两个分子量相近的组份。  相似文献   

5.
牛病毒性腹泻病毒基因组cDNA文库的构建   总被引:1,自引:0,他引:1  
以牛病毒性腹泻病毒(BVDV)┥nL株的基因组RNA为模板,经逆向转录酶作用,合成第一链cDNA,再以RNadse/H与DNA聚合酶I联合作用合成dscDNA,并以dC同聚物尾化。pUC8DNA在Pst I酶解后,以dG同聚物尾化,两者退火构成重组质粒,转化到E.coli JM101受体菌中,另以γ-^32P-ATP标记BVDV RNA制备探针,通过菌落原位杂交筛选重组子。酶切分配表明重组质粒插入  相似文献   

6.
通过有机试剂抽提,CF-11纤维素柱层析,从感染水稻齿叶矮缩病毒菲律宾分离株(RiceRaggedStuntVirus,Philippineisolate,简称RRSV-P)的水稻植株中获取该病毒的全基因组,即获得从Segment1到Segment10(S1-S10)的10条双链RNA(dsRNA),然后设计合适的引物,用RT-PCR方法得到S9的cDNA并将其克隆到pUC119质粒上扩增,以双链测序法测定该cDNA的全序列。同时又将此cDNA克隆到大肠杆菌表达质粒pGEX-3X上,在大肠杆菌菌株DE3中用IPTG诱导表达,经超声波破菌、离心、Glutathione-sepharose4B亲和层析,得到纯化的分子量为64kD的融合蛋白。  相似文献   

7.
用对流电泳提纯兔出血症病毒   总被引:2,自引:0,他引:2  
兔出血症病毒(RHDV)在pH8.6的琼脂糖凝胶上电泳,在负极侧有一血凝峰,免疫电镜观察有大硅RHDV颗粒,证实RHDV病毒粒子带正电荷。利用这一特性可用对流电泳提纯病毒。将抗体与病毒颗粒形成的沉淀带切下,作SDS-PAGE,经免疫转印出现6条区带,其中60kD的VP_1为主要结构多肽。用免疫复合物提取核酸,以狄高辛标记制成探针,能与病毒核酸和克隆的RHDVcDNA2.2kb片段和4.8kb片段杂交,探针灵敏度达pg水平。能用病毒核酸作模板制备探针,证实RHDV的核酸为DNA。  相似文献   

8.
本文发现线粒体H^+-ATPase复合体先用0.5ug/ml的DCCD(二环已基碳二亚胺预保温处理,再经12.5%(V/V)乙醇进一步保温处理,则乙醇可完全消除DCCD引起的H^+-ATPase的抑制效应。若H^+-ATPase用DCCD和乙醇同时预保温处理,则DCCD同样消失其抑制作用。用相同浓度的甲醇代替乙醇,则仅可部分的消除DCCD的抑制作用。用相同浓度的DMSO(二甲基亚砜)代替乙醇,则不  相似文献   

9.
杜氏盐藻细胞质膜具的氧化NAD(P)H,还原Fe(CN)^3-6和O2的氧化还原系统。当Fe(CN)^3-6浓度为0.6mmol/L,氧化NADH的Km为96μmol/L,Vmax为159nmol10^-8cellsmin^-1,最适pH为8.5。TritonX-100可促进NADH和Fe(CN)^3-6的氧化还原活性。NADH能促进藻细胞的氧吸收,最适pH为8.5。在无外源电子供体存在时,细胞质  相似文献   

10.
用Aedans标记肌动蛋白单体G-Actin上Cys374残基作为探针,研究了稀土离子Ce~(3+)与G-Actin的结合及引起的微构象变化。Ce~(3+)在低浓度(Ce~(3+)/Actin摩尔比<1)和Ca~(2+)竞争G-Actin上二价离子的高亲合位点。Ce~(3+)取代Ca~(2+)引起Aedans荧光强度增强与Mg~(2+)取代Ca~(2+)的结果相同。Ce~(3+)/Actin>l则导致Aedans荧光强度下降。说明Ce~(3+)在高低两种浓度条件下结合的位点及对Cvs374的微构象的影响不同。时间分辩测得的Aedans荧光寿命也支持这一结论。CD谱结果表明Ce~(3+)/Actin<0.4,Actin的二级结构增加,大于0.4又导致其失去。Ce~(3+)-Actin在有/无游离ATP时用聚合液诱导的聚合结果表明,无游离ATP时,极低浓度Ce~(3+)促进聚合,高浓度虽有促进但有所减弱;有游离ATP时,Ce~(3+)/Actin在实验范围内促进聚合。  相似文献   

11.
通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.  相似文献   

12.
The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.  相似文献   

13.
14.
龙胆科药用植物化学成分的研究现状   总被引:16,自引:0,他引:16  
龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。  相似文献   

15.
16.
真菌类遗传学分析的知识结构教学   总被引:5,自引:2,他引:3  
罗桂花 《遗传》2002,24(3):349-350
本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.  相似文献   

17.
Summary Embryogenic tissues of sugi (Cryptomeria japonica) were induced on a modified Campbell and Durzan (CD) medium containing 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 600 mg l−1 glutamine, and subcultured in the medium of the same composition for over 1 yr. This resulted in a mixed culture of embryogenic and non-embryogenic cells. When embryogenic cells were isolated and cultured independently, their capacity to form embryogenic aggregates was lost. Thus, the non-embryogenic cells present within a mixed culture system were essential to the formation of embryogenic aggregates. When embryogenic tissues were isolated and cultured independently on a high glutamine-containing (2400 mg l−1) medium, dry weights and endogenous levels of glutamine increased, and the tissue could generate a large number of embryogenic aggregates. Amino acid analysis of embryogenic and non-embryogenic cells from the maintenance culture indicated a higher level of glutamine was present in the latter. The high endogenous level of glutamine in the non-embryogenic portion of mixed cell masses may be the supplier of glutamine for maintaining the embryogenic property of the tissues.  相似文献   

18.
The review deals with study of enzymologic properties of a novel highly specific acetylcholinesterase substrate, N-(β-acetoxyethyl) piperidinium iodomethylate (“piperidylcholine”), and its 30 derivatives that were tested as effectors of cholinesterases of mammals and various species of Pacific squids. It was proven for the first time that responsible for specificity of action was structure of cyclic ammonium grouping of the alcohol part of molecule of the ester substrate. Analysis of specificity is performed based on enzymatic hydrolysis parameters—activity of catalytic center of cholinesterases and bimolecular constant of the reaction rate that are determined at optimal and low substrate concentrations. Among the specially synthesized group of thioester compounds there is revealed one more highly specific acetylcholinesterase substrate—N-(β-acetoxyethyl) piperidinium.  相似文献   

19.
Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m−2 s−1. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to Pfr.  相似文献   

20.
目的 针对医疗机构的合理用药水平进行评价研究。方法 根据医疗机构合理用药的具体要求,构建医疗机构合理用药评价指标体系,采用基于模糊群决策的方法和多指标评价分析法构建医疗机构合理用药评价模型。结果 构建了基于模糊群决策的医疗机构合理用药评价模型,并通过实例分析证明了评价模型的可行性。结论 建立的基于模糊群决策的医疗机构合理用药评价模型能够对医疗机构的合理用药水平进行科学评价,为提高医疗机构合理用药水平奠定基础。  相似文献   

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