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1.
用竹节花黄斑驳病毒(Commelina Yellow Mottle Virus,CoYMV)启动子-gus嵌合基因和CaMV35S-gus嵌合基因通过根癌土壤杆菌(Agrobacterium tumefaciens(Smith et Townsend)Conn)LBA4404介导分别转入棉花(Gossypium hirsutum L.cv.Jingmian7,J7G),诱导再生了棉花转基因植株。G  相似文献   

2.
表达barstar基因及bar基因的转基因油菜的研究   总被引:30,自引:0,他引:30  
从细菌Bacilusamyloliquefaciens染色体DNA中克隆了barnase抑制剂barstar的基因,构建了带有TA-29基因5′调控区(-1300-+3)与barstar基因编码区、CaMV35S启动子与除草剂抗性基因bar两个表达框架的植物表达质粒pBBS。以“双低”油菜“5-4”的子叶柄为受体,通过农杆菌介导的遗传转化,获得了在含有10mg/L卡那霉素和20mg/LPPT的筛选培养基上再生的转基因植株。PCR分析结果表明,barstar基因已整合到油菜染色体上;Northernblot检测表明,barstar基因及bar基因在转基因植物中得到了正确的调控与表达。以转基因油菜“5-4”为父本授粉给表达barnase基因的雄性不育植株,不育株能正常结实。  相似文献   

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提高菜心离体植株再生频率的研究   总被引:42,自引:0,他引:42  
AgNO3与ABA 相配合,在离体培养条件下从3个菜心(Brassica parachinensisBail.)品种(“49-19”、“60D”和“70D”)获得了高频率的植株再生。结果表明:在试验的3种外植体中,子叶-子叶柄再生能力最强。实生苗龄及接种方式影响植株再生频率。MS附加不同浓度的BAP和NAA,BAP 2 m g/L与NAA 1 m g/L配合效果最好,植株再生频率可达26.8% 。培养基中单独添加AgNO3 或ABA 均能促进植株再生,且AgNO3 作用优于ABA。AgNO3(4 m g/L)和ABA(0.5 m g/L)相配合获得了更高的植株再生频率:“49-19”达89% ,“60D”达84.3% ,“70D”达86% 。组织学研究表明,在本实验条件下菜心离体培养植株再生方式为外植体直接出芽。不定芽起源于子叶柄切口端维管组织的薄壁细胞;由此种细胞分裂形成分生细胞团,继而分化成芽。试管苗移入盆中获得成熟植株  相似文献   

4.
叶荣  于善谦 《病毒学报》1996,12(1):62-68
用芜菁花叶病毒辽宁分离物(TuMV-LN),山东分离物(TuMV-SD)和榨菜分离物(TuMV-ZC)作抗原,分别免疫BALB/c小鼠,经脾细胞与SP2/O-Ag14骨髓细胞融合,共获得7个单克隆抗体分泌细胞株,为研究3个分离物的抗原差异,用胰蛋白酶消化TuMV的外壳蛋白(CP)。分别形成4、2和1条降解带,经SDS-15%PAGE后,转移至硝酸纤维薄膜上,用3个分离物的抗血清和7种单隆抗体分别做  相似文献   

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转BmK IT4基因烟草的抗虫性   总被引:3,自引:0,他引:3  
用酶切方法从「pBS-BmK IT4质粒中获得BmK IT4基因片段,并构建CaMV 35S启动子下的BmK IT4基因表达质粒pE3-BmK IT4,以根癌土壤杆菌(Agrobacterium trmefaciens(Smith et Townsend)Conn)介导的叶盘法转化云烟(Nico-tiana tabacum L.)K326叶片,获得45株抗卡那霉素的再生植株。用这些再生植株进行抗虫  相似文献   

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在大肠杆菌中表达了马铃薯Y病毒中国分离物(PVY-C)复制酶NIb基因,并制备了其抗血清。利用PCR定点突变方法使NIb基因移码-1位,构建了移码-1位NIb基因(UN)的植物表达载体。通过土壤农杆菌(Agrobacterium tumefaciens LBA4404)介导转化烟草NC89,获得51株再生植株。对再生植株的分子检测结果表明,转基因烟草中检测到UN基因相应的RNA转录产物,3推测该基  相似文献   

7.
黄瓜花叶病毒(CMV)运动蛋白基因介导的抗病性   总被引:4,自引:0,他引:4  
利用Fny_CMV株系RNA3cDNA克隆,构建了含有全长和编码区缺失501个核苷酸的运动蛋白(MP)基因植物表达载体pBMPR和pBMPK。在土壤农杆菌(Agrobacteriumtumefaciens(SmithetTownsend)Conn)LBA4404介导下转化烟草(NicotianatabacumL.)品种“NC89”,分别经Southernbloting、RT_PCR或Westernbloting分析,外源基因已整合到再生植株中并得到表达。抗病性分析表明,含有缺失型MP基因的R0代转基因植株抗性较好,接种50d后,10株转化植株中仍有5株不表现症状。在自然发病条件下,这5个含有缺失型MP基因转基因株系在R1代都表现了一定的抗病性。抗性主要表现为症状出现推迟,严重度减轻。利用PCR筛选、种子卡那霉素抗性试验和温室抗病性测定等方法,初步认为R2代转基因烟草K_6_5株系为转基因抗病纯合系。而含有全长MP基因的R0代转化植株,前期没有表现明显的抗病性,但在接种40d后部分发病植株有恢复健康的趋势。  相似文献   

8.
将抗病毒的CMV-cp基因和抗虫的Bt-toxin基因依次插入到植物表达载体PE3的HindⅢ和KpnⅠ位点,通过菌落原位杂交筛选和酶切鉴定,然后以土壤农杆菌GV311-SE介导转化番茄,胭脂碱检测,染色体DNA的点杂交及PCR扩增证明CMV-cp基因和Bt-toxin基因已同时导入转化再生的番茄植株。RNA点杂交证明CMV-cp基因和Bt-toxin基因已在转基因番茄植株中同时获得表达。  相似文献   

9.
叶萍  李燕 《病毒学报》1998,14(3):215-220
将Epstein-Barr病毒(EBV)膜抗原(MA)BLLF1基因,插入含有CMV启动子的真核表达载体pcDNA3下游BamHI位点,构建成真核表达质粒pcDNA3-MA。将纯化的DNA注射Balb/c小鼠股四头肌。经免疫的动物产生抗EB病毒MA特异性的抗体和中和抗体,依赖抗体细胞介导的细胞毒作用(ADCC),特异性T淋巴细胞增生性反应及细胞毒性T淋巴细胞(CTL)杀伤作用。基因免疫与基因-蛋白  相似文献   

10.
动脉平滑肌细胞(SMC)是动脉粥样硬化(AS)斑块中的主要细胞,它的增殖在AS形成过程中极其重要。脂蛋白和氧化修饰型脂蛋白对SMC增殖的影响以及SMC增殖与原癌基因异常表达的关系是当前AS发病机制研究的热点之一。我们在建立人主动脉SMC体外培养方法的基础上,观察了LDL,VLDL及HDL和相应的氧化修饰型脂蛋白对培养人SMCfos,myc,erb-B原癌基因转录表达的影响。结果表明:①HDL对SMCfos,myc基因表达无影响;②LDL和VLDL有使这些基因表达增加的趋势,但与对照比较差异不显著(P>0.05);③OX-VLDL,OX-VLDL和OX-HDL有使SMCfos,myc基因表达显著增强的作用(P<0.01),且其作用较相应的天然脂蛋白大(P<0.01).上述结果说明:LDL,VLDL,OX-LDL,OX-VLDL和0X-HDL的致AS作用可能与刺激SMCfos和myc癌基因表达增加有关。  相似文献   

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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.  相似文献   

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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.  相似文献   

18.
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.  相似文献   

19.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
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  相似文献   

20.
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.  相似文献   

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