云南省昆明地区番茄斑萎病毒核衣壳蛋白和运动蛋白变异分析

为了明确对番茄斑萎病毒(tomato spotted wilt virus,TSWV)免疫的番茄YNAU335自交系表现出TSWV感病症状(抗性被打破)的原因,在排除YNAU335自交系不纯和或混杂其它感病番茄材料的因素外,选取96172I(感病)和YNAU335(抗性被打破)自交系感病植株,进行TSWV核衣壳蛋白(nucleocapsid protein,NP)和运动蛋白(movement protein,MP)基因的RT-PCR检测,并对阳性克隆进行基因测序分析。结果表明:(1)2个自交系中均克隆出TSWV的NP和MP基因,共获得5条NP(登录号:MK628735～MK628739)和3条MP(登录号:MK883723、MK883724和MK887284)多态性基因序列。(2)96172I感病材料中克隆出以上所有基因序列,YNAU335感病材料中克隆出其中的3条NP和1条MP基因序列。(3)对YNAU335中TSWV特有的NP和MP氨基酸突变位点进行分析,结果发现4个特异突变位点可能与打破YNAU335抗性有关,4个突变位点分别为:NP 18位氨基酸G突变为V,36位T突变为I,39位L突变为R,MP 274位E突变为K。(4)系统发育分析显示,5条NP和3条MP与云南省已登记的NP和MP聚类在不同的分支,表明云南省昆明地区TSWV存在丰富的遗传多样性。     

重组靶向核糖体失活蛋白luffin-α-NGR的制备及抗肿瘤活性评价

将丝瓜籽核糖体失活蛋白luffin-α与肿瘤靶向肽NGR融合,制备luffin-α-NGR重组蛋白,并检测其对肿瘤细胞与血管生成的抑制活性.通过引物设计及PCR扩增获得luffin-α-NGR融合基因,与pGEX-6p-1载体连接后获得pGEX-6p-1/luffin-α-NGR重组质粒,质粒转入大肠杆菌(Escher...     

西花蓟马酵母双杂交文库及TSWV膜蛋白诱饵载体的构建

【目的】为筛选西花蓟马Frankliniella occidentalis与番茄斑萎病毒的互作蛋白。【方法】利用MakeYour Own"MatePlate?"Library System构建西花蓟马酵母双杂交初级cDNA文库以及Y187酵母次级文库,利用Matchmaker Gold Yeast Two-Hybrid System构建TSWV膜蛋白GN及GC诱饵载体。【结果】建立的西花蓟马初级cDNA文库库容为5.6×106 cfu,其插入片段平均长度大于1 000 bp,重组率约为100%。建立的Y187酵母次级文库转化效率为5×106cfu/μg,文库滴度为2.97×108。构建的pGNKT7-GN及pGBKT7-GC诱饵载体能够在Y2HGold酵母菌株中正确表达,无自激活活性且无毒性。【结论】成功构建了西花蓟马酵母双杂交文库以及番茄斑萎病毒膜蛋白诱饵载体,可用于后续筛库实验。     

番茄斑萎病毒GN与西花蓟马互作蛋白的初步筛选

[目的]西花蓟马Frankliniella occidentalis (Pergande)是番茄斑萎病毒(Tomato spotted wilt orthotospovirus,TSWV)的主要传播媒介,以循环增殖方式传播TSWV,但在传播过程中参与的互作蛋白尚不清楚。本研究以TSWV的外鞘糖蛋白GN (GlycoproteinN)为诱饵筛选与西花蓟马互作的蛋白,为阐明TSWV与西花蓟马的互作机制提供依据。[方法]构建以pPR3-N为载体的西花蓟马泛素分裂酵母双杂交膜系统cDNA文库,利用Gene Ontology (GO)通路注释互作蛋白,分析其生物学功能。[结果]西花蓟马cDNA文库库容为3.2×10~6,除去重复序列、载体序列和移码序列,筛选到74个与G_N互作的蛋白,参与了细胞过程、代谢过程、生物调节过程等12种生物过程。[结论]成功构建了西花蓟马酵母双杂交膜体系cDNA文库,筛选到与TSWV GN互作的蛋白,为进一步研究TSWV与西花蓟马的互作机制奠定了基础。     

银川番茄斑萎病毒的分子鉴定

为明确银川番茄(Lycopersicon esculentum)是否遭受了番茄斑萎病毒(TSWV)的危害, 采用国家标准TSWV RT- PCR检测技术对银川番茄上采集的14份疑似感染TSWV病叶样本进行分子鉴定, 对克隆得到的核衣壳蛋白基因N (Nucleocapsid)序列进行多序列比对和系统进化树分析, 随后对PCR阳性样本进行蛋白检测。结果表明, 14份病叶样本中有8份扩增出长度为394 bp的TSWV N基因序列, 且8条序列完全一致; 获得的银川番茄TSWV分离物与云南番茄、中国莴苣(Lactuca sativa)、中国鸢尾(Iris tectorum)和重庆辣椒(Capsicum annuum) TSWV分离物相对近缘, 与山东、黑龙江和北京等地及国外TSWV分离物相对远缘; 利用TSWV的抗体通过Western blot对8个PCR阳性样本进一步检测, 结果也证实8个阳性样本中存在TSWV感染。该研究首次通过分子鉴定及蛋白检测证明银川番茄上存在TSWV感染, 需要加快抗TSWV番茄品种的选育工作。     

用ELISA和Dot-ELISA方法检测植物病原的比较研究

比较了ELISA和Dot-ELISA方法检测番茄巨芽类菌原体(Tomato Big Bud Mycoplatma-Like Organism,TBB-MLO)、番茄斑萎病毒(Tomato Spotted Wilt Virus,TSWV)和青枯假单胞菌(Pseudomonas solanacearum)的差异,结果表明,两种方法对番茄斑萎病毒无明显差异,对番茄巨芽类菌原体,用Dot-ELISA比用ELISA的检测灵敏度高50—100倍,对青桔假单胞菌,用Dot-ELISA比用ELISA检泓抗原     

miR-769-3p 对甲型 H1N1流感病毒核蛋白表达的调控

目的:预测靶向甲型流感病毒核蛋白(NP)基的微小 RNA(miRNA),并检测其对 NP 表达的影响.方法:从miRBase 数据库中获取人成熟 miRNA 序列,利用 miRanda 软件预测潜在靶向流感病毒 A/FM/1/47(H1N1) NP 基的人 miRNA;通过双萤光素酶报告基系统及 Western 印迹验证所预测的 miRNA 对 NP 表达的影响.结果:用 miRanda软件在流感病毒 A/FM/1/47(H1N1) NP 基上预测得到分值及最小结合自由能均较好的 miR-769-3p;双萤光素酶报告基结果显示 miR-769-3p 能显著降低报告基载体萤光素酶的表达;Western 印迹结果显示 miR-769-3p 能明显抑制 NP 的表达,但突变 NP 基上的 miR-769-3p 结合位点后,miR-769-3p 不能抑制 NP 的表达.结论:miR-769-3p 可靶向流感病毒 A/FM/1/47(H1N1) NP 基并抑制 NP 的表达,为抗甲型流感病毒的 miRNA 药物研发提供了据和潜在药物靶标.     

核蛋白MARVELD1与核质转运受体蛋白Importin β1相互作用的鉴定

核蛋白MARVELD1（MARVEL domain containing 1）是一个在多种肿瘤中表达下调的肿瘤相关基因. 为寻找其相互作用分子,构建pGEX-4T-2/MARVELD1重组体并在大肠杆菌中成功表达GST-MARVELD1融合蛋白. 采用GST pull-down 结合LC-MS/MS（液相色谱-串联质谱）的方法对MARVELD1蛋白的相互作用分子进行筛选,发现了16个与MARVELD1相互结合的蛋白. 进一步的免疫共沉淀实验证实, MARVELD1与核质转运受体蛋白importin β1能够相互作用,说明MARVELD1可能参与了importin β1的部分生物学作用, 或是它通过与importin β1结合而进入细胞核. 研究结果为进一步分析MARVELD1和importin β1的生物学功能奠定了基础.     

用人MHC转基因小鼠模型鉴定高致病禽流感病毒核蛋白CTL表位

目的:筛选高致病禽流感病毒核蛋白(NP)中可用于高致病禽流感病毒感染检测或疫苗设计的CTL表位,为评价疫苗接种效果和开发新型疫苗奠定基础。方法:根据NCBI公布的NP的核苷酸序列设计特异性引物,以2006年深圳株高致病禽流感H5N1病人分离的病毒cDNA为模板扩增NP全长基因(1500 bp)并测序。通过生物信息学方法,预测NP氨基酸序列中潜在的HLA-A觹0201限制性表位。构建重组pJW4303-NP核酸疫苗并肌肉免疫HLA-A2/DP4转基因小鼠,利用ELISPOT法筛选特异性CTL表位。结果:克隆了2006年深圳株高致病禽流感NP基因,构建的重组pJW4303-NP核酸疫苗能在体外COS-7细胞中表达,免疫小鼠后能引起小鼠产生特异性的体液免疫和细胞免疫。结论:生物信息学和转基因小鼠模型筛选相结合的方法,能用于高致病性禽流感核蛋白CTL表位的筛选。     

大肠杆菌可溶性表达人鳞状上皮细胞癌抗原的制备及应用

旨在建立基于大肠杆菌表达系统的高效可溶性表达人鳞状上皮细胞癌抗原(SCCAg)方法,获得具有较好活性的重组SCCAg抗原并应用于建立抗原检测方法。基于pGEX-6P-1载体和大肠杆菌E.coliER2566菌株开展重组SCCAg抗原可溶性表达纯化方法研究,评价纯化抗原活性,筛选特异性单克隆抗体,初步建立并评价SCCAg抗原检测方法。结果显示,pGEX-6P-1载体和E.coliER2566菌株可用于建立较高效的可溶性表达和纯化SCCAg抗原的方法,获得了具有较高纯度和活性的重组SCCAg抗原,筛选获得特异性单克隆抗体并初步建立了SCCAg管式化学发光检测方法。建立了有效的基于大肠杆菌表达系统的可溶性表达和纯化SCCAg的方法。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.