984 resultados para bidimensional electrophoresis


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本文以复苏植物牛耳草Boea hygrometrica成熟植株的离体叶片为试材,对比非复苏植物烟叶唇苣苔Chirita heterotricha, 以光合作用在脱水-复水过程中的变化为切入点,从生理水平上探讨其脱水保护位点:应用mRNA差异显示技术,从分子水平上探讨其脱水保护机制。 光合放氧速率、快速荧光诱导动力学、慢速荧光诱导动力学、荧光发射光谱、荧光激发谱的结果表明,相对于烟叶唇柱苣苔,脱水对牛耳草净光合速率、PS II和PS I光化学活性、电子传递、光合磷酸化及CO_2固定的影响有一个共同的特点,即脱水时迅速降低,复水后恢复能力强。通过非变性绿胶的研究牛耳草叶片类囊体膜叶绿素-蛋白复合体在脱水-复水过程中保持高度稳定。色素含量分析表明牛耳草的叶绿素含量在脱水-复水过程中也相对稳定。这些特征可能是牛耳草叶片光合作用脱水保护机制的一部分。 SDS-PAGE和IEF电泳结果表明,牛耳草脱水复苏过程中蛋白质表达有差异,或增或减,并分别发现了一条(SDS-PAGE)和两条(IEF)在脱水过程中特异出现的蛋白质。 本文以银染法代替放射自显影用于mRNA差异显示,不但简化了实验步骤,缩短了实验周期,而且在不降低灵敏度的前提下避免了放射性危害,降低了实验成本。本文证明了mRNA差异银染显示法用于复苏植物牛耳草脱水-复水过程中基因表达变化的研究是可行的。 mRNA差异银染显示法揭示牛耳草耐脱水复苏机制涉及到基因表达的调控。脱水-复水过程中差异表达的基因有6种,其中脱水特异诱导表达的13个cDNA所相应的基因、脱水上调节的15个cDNA所相应的基因可能参与牛耳草叶片脱水保护机制,复水特异诱导的8个cDNA的所相应基因可能参与牛耳草复水后的修复机制。2个脱水特异诱导表达的cDNA片段进行了克隆和测序。

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Little is known about the ocean distributions of wild juvenile coho salmon off the Oregon-Washington coast. In this study we report tag recoveries and genetic mixed-stock estimates of juvenile fish caught in coastal waters near the Columbia River plume. To support the genetic estimates, we report an allozyme-frequency baseline for 89 wild and hatchery-reared coho salmon spawning populations, extending from northern California to southern British Columbia. The products of 59 allozyme-encoding loci were examined with starch-gel electrophoresis. Of these, 56 loci were polymorphic, and 29 loci had P0.95 levels of polymorphism. Average heterozygosities within populations ranged from 0.021 to 0.046 and averaged 0.033. Multidimensional scaling of chord genetic distances between samples resolved nine regional groups that were sufficiently distinct for genetic mixed-stock analysis. About 2.9% of the total gene diversity was due to differences among populations within these regions, and 2.6% was due to differences among the nine regions. This allele-frequency data base was used to estimate the stock proportions of 730 juvenile coho salmon in offshore samples collected from central Oregon to northern Washington in June and September-October 1998−2000. Genetic mixed-stock analysis, together with recoveries of tagged or fin-clipped fish, indicates that about one half of the juveniles came from Columbia River hatcheries. Only 22% of the ocean-caught juveniles were wild fish, originating largely from coastal Oregon and Washington rivers (about 20%). Unlike previous studies of tagged juveniles, both tag recoveries and genetic estimates indicate the presence of fish from British Columbia and Puget Sound in southern waters. The most salient feature of genetic mixed stock estimates was the paucity of wild juveniles from natural populations in the Columbia River Basin. This result reflects the large decrease in the abundances of these populations in the last few decades.

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盐角草(Salicornia europaea L.)是世界上最抗盐的高等植物之一。应用蛋白质组学方法对其抗盐性进行研究,对于我们理解植物抗盐机理和改进作物耐盐性都有重要意义。双向电泳是蛋白质组学的核心技术,样品制备是双向电泳的关键步骤。盐角草是一种聚盐的真盐生高等植物,其体内除含有多种次生代谢物质外还含有大量盐分,而盐离子的存在严重干扰等电聚焦的进行,其蛋白质提取较其他植物更为困难。因此,在进行蛋白质组学研究之前,有必要对其蛋白质提取方法进行摸索,建立一个高效的双向电泳体系。   比较了三氯乙酸/丙酮沉淀法(TCA)、三氯乙酸沉淀法(E-TCA)和酚抽法(Phe)三种方法对盐角草蛋白的提取效果。提取700mM处理2d的盐角草幼苗蛋白时,三种方法分别得到579,343和535个蛋白点;TCA和E-TCA法所得图谱均存在严重的横向纹理,Phe法所得图谱则背景干净,基本上没有纹理。说明Phe法不仅能很好地提取盐角草蛋白,而且能有效去除样品中的盐分。对200mM处理90d的盐角草蛋白的提取也证实了这一点。比较了不同沉淀剂对Phe法蛋白提取效果的影响,结果表明,甲醇不能代替乙酸铵甲醇溶液。对Phe法的提取液进行了改进,所得图谱背景更加清晰,蛋白点数增加。此外,还对聚焦时间,上样量和染色方法进行了改进优化,建立了盐角草双向电泳体系。   本研究表明,Phe法适合于盐角草双向电泳样品的制备,这为其他盐生植物以及嗜盐微生物蛋白质的提取提供了重要参考。   

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本文以西藏高原不同海拔高度八个居群的川滇高山栎和一个 居群的通麦栎为研究对象,应用同工酶电泳和形态指标的统计方 法,阐明了遗传多样性随着海拔高度的变化规律:海拔2400-3300 m的川滇高山栎的遗传变异水平较高,而海拔3800 m以及海拔 2200 m居群的遗传变异水平都有降低的趋势。本文还发现人为干 扰,日照多少等因素均对遗传变异水平有影响。通过遗传相似系数的比较,可以把通麦栎同川滇高山栎区别开来。形态指标同样能反映居群随海拔高度的变化趋势以及发育的状况。

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Electrophoretic and serological studies of foot muscle protein of three species of Cerithiacea (Telescopium telescopium, Cerithidea fluviatilis and C. obtusum) were carried out to understand their relationships. Living specimens were collected from mud flats and mangrove swamps off Portonovo. Polyacrylamide electrophoresis of proteins from foot muscle extract of T. telescopium, C. fluviatilis and C. obtusum showed that the former had a different densitometric profile as well as more number of protein bands; but the later two species showed a closer related pattern as well as lesser number of protein bands. At the same time these two species are distinguished from each other in their total number of bands and Rf values. Immunological studies using micro-Ouchterlony double diffusion tests which absorbed antiserum indicated that C. fluviatilis and C. obtusum were more closely related as revealed by an identity reactions than T. telesopium as shown by non-identity reactions. Results are discussed in relation to ecological and morphological adaptations

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植物与昆虫的互作关系是个长期进化的过程,虫害给农业生产带来巨大损失。本研究以甘蓝型油菜(Brassica napus)为例,研究了不同环境条件和遗传背景下外源基因的表达与效用,同时利用蛋白质组技术,研究了虫害损伤模拟条件下植物可能存在的内源抗性机制。甘蓝型油菜中转入了人工合成的Bt(Bacillus thuringiensis)杀虫基因,能使植物产生抗虫蛋白抵御虫害。我们在湖北湖南两个实验点进行了大田实验,按植株生长发育的4个不同时期从转基因植株的叶片上采样,研究抗虫蛋白在植物体内的表达动态。植株顶部第三片展开叶的Bt毒蛋白浓度在结荚期前随植物生长而不断增加,而在结荚期出现或增或减的现象。采样叶片的可溶性总蛋白浓度含量一直呈增加的趋势,直到结荚以后出现含量的明显降低。同时,收集了转基因油菜与湘油15号在田间自然杂交形成的杂交后代种子用于栽培,用GFP仪检测杂交后代的绿色荧光蛋白(green fluorescent protein),并用聚合酶链式反应(polymerase chain reaction, PCR)检测并确认带有转基因的杂交植株。为了检测带有转基因的杂交后代油菜中Bt毒蛋白的杀虫效率,用对Bt毒蛋白敏感的试虫品系——初孵棉铃虫幼虫(Helicoverpa armigera)进行杀虫活性检测实验。结果表明,携带Bt基因的杂交湘油及其转基因亲本对试虫的体重增长量均产生了负面影响,可以推断在调查取样的植株生长发育阶段,转基因杂交后代与其转基因亲本植株的杀虫效率没有显著差异。转基因植物及其杂交后代中抗虫蛋白的持续表达及田间带有转基因的自播植物的出现会使害虫产生耐受抗性的潜在可能性增加。 相对于人为增加的抗虫基因,植物在长期对抗昆虫的过程中也进化形成了自我防御机制,能够产生特异的抗性蛋白来应对昆虫的取食。本研究用机械损伤模拟害虫取食,对比了油菜受到物理损伤前后可溶性总蛋白的含量变化并试图通过蛋白质组学技术来检测可能发生变化的蛋白质。Bradford定量测定发现,同一植株同一叶片损伤前后可溶性总蛋白含量差异显著,损伤后蛋白表达量显著增高。蛋白质组双向凝胶电泳及其差异分析显示,损伤前后有8个蛋白质点发生明显的上调或下调。选择其中2个差异蛋白点经过MALDI-TOF质谱鉴定,它们分别是Rubisco小亚基前体以及果糖-1,6-二磷酸醛缩酶和粪卟啉-3-氧化酶的混合物,这些蛋白质在其他植物的抗逆研究中也有报道,它们可能在油菜叶片应答机械损伤过程中对维持植物的生理功能也有重要作用。

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水稻既是我国三大粮食作物之一,又是基因组学研究的模式材料,在生产实践和科学研究中都占有极其重要的地位。基因组学研究取得的巨大成就以前所未有的深度和广度推动了生命科学各个研究领域的飞速发展。水稻基因组的破译是水稻科学研究的重要里程碑,同时也宣告了功能基因组学时代的到来。蛋白质组学是研究细胞内全部蛋白质的动态表达及其相互关系的新兴学科,是功能基因组学研究的重要组成部分和战略制高点。 本论文采用高分辨率的蛋白质双向电泳分离技术和高通量的蛋白质质谱分析技术以及生物信息学等手段,开展水稻灌浆期茎蛋白质组表达模式和水稻幼苗脱黄化过程的比较蛋白质组学研究,探讨茎生长发育规律和水稻应答光信号相关蛋白质及其网络调控机制,是学科前沿与实际应用的有机结合,在科研和生产实践中都具有重要的意义。 首先,分别构建了灌浆期水稻顶端茎段和水稻黄化幼苗的蛋白质组表达谱。并对其中185个目的蛋白点进行了MALDI-TOF/MS分析和数据库检索鉴定。共有149个蛋白质得到了鉴定,蛋白质鉴定的成功率为80.5%。这些被鉴定的蛋白质分属118个基因的表达产物,根据它们功能可以分为13种不同的类别,其中绝大多数为能量产生和代谢以及抗性相关的蛋白质。 在水稻灌浆期顶端茎段表达的蛋白质中,与能量和物质代谢相关的蛋白质例如ATPase、磷酸丙糖异构酶,6-磷酸葡萄糖异构酶等占有很高比例,说明茎段组织中具有很强的代谢活动。与生长发育相关的蛋白质包括beta-tubulins、无机焦磷酸酶(inorganic pyrophosphatase)、液泡质子ATP酶(vacuolar proton-ATPase)以及UDP葡萄糖焦磷酸酶等的大量累积,显示出顶端茎段细胞分裂和生长迅速;同时,贮存多糖和结构多糖也在旺盛合成。G蛋白、GDP释放抑制因子等信号传导蛋白以及苯丙氨酸氨解酶、谷胱苷肽S转移酶(glutathione S-transferase,GST)、抗坏血酸过氧化酶(ascorbate peroxidase,APX)以及超氧化物歧化酶(superoxide dismutase,SOD)等抗性相关蛋白质在该时期丰度表达,表明在灌浆期水稻顶端茎段能够迅速感受并传递外界信号,从而使得其在遭受胁迫时能够立刻启动抗逆防御系统,最大限度地降低不利环境对种子发育的影响。 在黑暗中萌发和生长的水稻黄化幼苗随着光照时间(0~24小时)的延长,能通过双向电泳后检测到的蛋白质逐渐变少,24小时后趋于稳定,相当于正常光照条件下生长的水稻幼苗蛋白质组表达谱。进一步分析表明,在黄化苗中,分解代谢及能量产生相关的蛋白如丙糖磷酸异构酶、琥珀酰辅酶A连接酶、异戊酰辅酶A脱氢酶与ATPase等的表达量比较丰富;另外,还可能启动了脂肪酸的α氧化分解途径,以供黑暗中生长所需的物质和能量。当黄化幼苗光照后,与光合作用及物质合成相关的一些蛋白质表达量增加,而那些分解代谢相关酶类则有所下降。同时,鸟核苷酸结合蛋白β亚基类似蛋白、20S proteasome以及Bowman Birk trypsin inhibitor等信号传递及抗性相关蛋白随着光照时间的延长而减少,说明黑暗胁迫条件下水稻幼苗启动了相关的抗逆途径。叶绿素合成途径中的蛋白酶胆色素原脱氨基酶和金属鳌合酶在脱黄化过程中表达量有所下降,可能是因为叶绿素合成产物具有反馈抑制作用。 本研究首次利用蛋白质组学方法来解析水稻灌浆期茎蛋白质组表达模式和水稻黄化幼苗响应光因子的蛋白质组变化情况,鉴定了一些有价值的蛋白质,并得到了它们的表达特点和相关数据,为更好地理解水稻顶端茎秆的生长特点和功效、水稻应答黑暗胁迫和光形态建成以及光合作用机理等提供了分子证据。

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The Annual report covers Research work of the Organization carried out during the period 1975. Its explains the following research work: Haplochromis Studies, Electrophoresis,The Ecology of Haplochromis in the northern waters of Lake Victoria Limnology, Aquatic Pollution and Biochemical Studies The Biology of Synodontis in Lake Victoria Riverine Fisheries, Inshore Fishery of the Kenyan-Waters of Lake Victoria Biostatistics, the Inshore Fisheries of the Western part of Lake Victoria, The Offshore Fisheries of Kenyan Waters of Lake Victoria Lake Mobutu Sese Seko: Stock Assessment and Ecological Studies Fishery Economics, The Biology of Bagrus docmac in Lake Victoria Fishery Resource Surveys of Lake Wamala and Kijanebalola

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文采用蛋白电泳技术研究滇南小耳猪血液蛋白多态性。共分析了滇南小耳猪32个遗传位 点,其中AKP、CAT、ES、PA、6PGD和TF等6个位点检测到多态性,多态位点百分比P=0.1875,平均 杂合度H=0.0712。结果表明滇南小耳猪的血液蛋白多态程度较高,反映在蛋白质水平上的遗传多样 性较为丰富。

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In this study, protein electrophoresis was assayed to detect genetic variation in Genus Nycticebus. A total of 29 samples (2 N. coucang and 27 N. pygmaeus) were analyzed for 42 genetic loci. In the 27 samples of N. pygmaeus, 4 loci were observed to be polymorphic. Therefore, the estimated P value (proportion of polymorphic loci) is 0.095, the A value (average number of alleles each locus) is 1.045, and the H value (mean individual heterozygosity) is 0.040. After comparing the H of N. pygmaeus with those of other primates reported, we found that the protein variation in N. pygmaeus is slightly lower than the average level. Additionally, we also observed obvious allele difference between N. pygmaeus and N. coucang. There are no shared alleles between these two species in eight loci. The NEI's genetic distance between them was calculated as 0.2541, which falls in the spectrum of genetic difference between species in primates.

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Amphioxus is a crucial organism for the study of vertebrate evolution. Although a genomic BAC library of Branchiostoma floridae has been constructed, we report here another BAC library construction of its distant relative species Branchiostoma belcheri. The amphioxus BAC library established in present study consists of 45,312 clones arrayed in one hundred and eighteen 384-well plates. The average insert fragment size was 120 kb estimated by Pulsed Field Gel Electrophoresis (PFGE) analysis of 318 randomly selected clones. The representation of the library is about 12 equivalent to the genome, allowing a 99.9995% probability of recovering any specific sequence of interest. We further screened the library with 4 single copied Amphi-Pax genes and identified total of 26 positive clones with average of 6.5 clones for each gene. The result indicates this library is well suited for many applications and should also serve as a useful complemental resource for the scientific community.

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Genetic variation of four hatchery stocks of Thai pangas, Pangasius hypophthalmu [sic] of Bogra region, Bangladesh was studied from 1 January 2002 to 31 December 2003. Muscle samples were collected for allozyme analysis from four (Bhai-Bhai, Jahangir, Belal and Bhai-Bon) different hatchery populations. For allozyme electrophoresis, eight enzymes were used and 11 loci viz. Adh-1*, Est-1*, GJpdh-1*, Gpi-1*, Gpi-2*, Jdhp-1*, Ldh-1*, Ldh-2*, Mdh-1*, Mdh-2*and Pgm* were identified, of which three loci (Est-1*, Gpi-2*, G3pdh-1 and Pgm*) were polymorphic in all the four populations. The mean proportion of polymorphic loci per population and the mean proportion of heterozygous loci per individual was 36.36% and 13.33, respectively for all the population studied. The highest variability measured by the mean number of alleles per locus was 1.545 in Bhai-Bon hatchery population. Based on Nei's (1972) genetic distance, the dendrogram (UPGMA) shows that four populations have made two clusters by D-value (D=0.043). Bhai-Bhai and Jahangir hatchery populations have made cluster-I, and Belal Uddin and Bhai-Bon hatchery populations formed cluster-II. Among the four populations, BhaiBhai and Jahangir hatchery populations were differentiated from each other by the D-value of 0.013, and Belal Uddin and Bhai-Bon populations were differentiated from each other by the D-value of 0.002, which suggests that the four populations may be fallen into the local population or race.

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Genetic and morphological characters of four hatchery population (Shambhuganj, Brahmaputra, Anudan and Bhai-Bhai) of Thai pangas, Pangasius hypophthalmus in Mymensingh region of Bangladesh was studied using morphological characters and allozyme markers from 29 November 2001 to 29 November 2002. A total of 14 morphometric and 6 meristic characters were verified, among which 3 morphometric (BDA, PELFL and HW) and 2 meristic characters (AFR, CFR) of Anudan hatchery population were found to be significantly higher (p>0.001) than those of the other three hatchery populations. Brahmaputra hatchery population was also significantly higher in two meristic characters (PCFR and CFR). For allozyme electrophoresis nine enzyme markers were used viz.: Esr-1*, G3pdh-2*, Gpi-1*, Gpi-2*, Ldh-1*, Ldh-2*, Mdh-1*, Mdh-2* and Pgm* where three loci (Esr-1*, Gpi-2* and Pgm*) were polymorphic (p>0.95) in Anudan and Brahmaputra hatchery populations. The mean proportion of polymorphic loci per population was higher (33.3%) in Brahmaputra and Anudan hatchery populations. Also the expected heterozygosity levels were 0.149 and 0.177 in Brahmaputra and Anudan hatchery populations, respectively. Based on Nei's (1972) genetic distances, the UPGMA dendrogram grouped the populations into two clusters. The Brahmaputra and Anudan populations are in one group; Shambhuganj, and Bhai-Bhai populations are in the second group. High genetic variation in Thai pangas was observed in the Brahmaputra and Anudan hatchery populations and less variation in the other two hatchery populations.

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A specific blood coagulation factor X activator was purified from the venom of Ophiophagus hannah by gel filtration and two steps of FPLC Mono-Q column ion-exchange chromatography. It showed a single protein band both in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and alkaline polyacrylamide gel electrophoresis. The mol. wt was estimated to be 62,000 in non-reducing conditions and 64,500 in reducing conditions by SDS-PAGE. The isoelectric point was found to be pH 5.6. The enzyme had weak amidolytic activities toward CBS 65-25, but it showed no activities on S-2266, S-2302, thrombin substrate S-2238, plasmin substrate S-2251 or factor Xa substrate S-2222. It had no arginine esterase activity toward substrate benzoylarginine ethylester (BAEE). The enzyme activated factor X in vitro and the effect was absolutely Ca2+ dependent, with a Hill coefficient of 6.83. It could not activate prothrombin nor had any effect on fibrinogen and thus appeared to act specifically on factor X. The procoagulant activity of the enzyme was almost completely inhibited by serine protease inhibitors like PMSF, TPCK and soybean trypsin inhibitor; partially inhibited by L-cysteine. Metal chelator EDTA did not inhibit its procoagulant activity. These results suggest that the factor X activator from O. hannah venom is a serine protease.

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A blood coagulation factor IX-binding protein (TSV-FIX-BP) was isolated from the snake venom of Trimeresurus stejnegeri. On SDS-polyacrylamide gel electrophoresis, TSV-FIX-BP showed a single band with an apparent molecular weight of 23,000 under non-reducing conditions. and two distinct bands with apparent molecular weights of 14,800 and 14,000 under reducing conditions. cDNA clones containing the coding sequences of TSV-FIX-BP were isolated and sequenced to determine the structure of the precusors of TSV-FIX-BP subunits. The deduced amino acid sequences of two subunits of TSV-FIX-BP were confirmed by N-terminal protein sequencing and trypsin-digested peptide mass fingerprinting. TSV-FIX-BP was a nonenzymatic C-type lectin-like anti-coagulant. The anti-coagulant activity of TSV-FIX-BP was mainly caused by its dose dependent interaction with blood coagulation factor IX but not with blood coagulation factor X. (C) 2003 Elsevier Science Ltd. All rights reserved.