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1.
烟草脱外壁花粉的电激基因转移   总被引:4,自引:0,他引:4  
以 β-葡糖苷酸酶 GUS 基因作为报告基因 ,通过瞬间表达的检测 ,比较了烟草 Nicotianatabacum L . 脱外壁花粉、未萌发与萌发花粉的电激导入效果 ,探讨了不同电激条件及启动子对外源基因瞬间表达的影响 .结果表明 :当脉冲时间常数为 13 ms时 ,导致脱外壁花粉和萌发花粉生活力下降约50 %的电场强度分别为 750 V/ cm和 12 50 V/ cm,在此条件下电激 ,二者的导入效果最好 .脱外壁花粉的GUS基因表达水平约为萌发花粉的 5倍、花粉粒的 30倍 .玉米花粉特异启动子 Zm13- 2 60 能启动 GUS基因在脱外壁花粉和萌发花粉中高效表达 ,而 Ca MV 35S的启动活性很低  相似文献   

2.
构建了来自根癌农杆菌(Agrobacterium tum efaciens) T-DNA 的细胞分裂素基因(T-cyt)启动子驱动下的GUS基因的表达质粒,并用以转化烟草(Nicotiana tabacum cv. W 38)和马铃薯(Solanum tubero-sum L. cv. Desiree),研究其在转基因植物中表达的定位。结果表明,T-cyt启动子在转基因植株的根、茎、叶、块茎和萌发的种子中均可表达。其中在茎和块茎中的表达是不均一的:在维管束部分表达较强,在侧芽或叶柄的生长点及块茎的芽生长点表达活性较高。此外,在培养基中加入0.1 m g/LBAP,转基因烟草茎中GUS基因的表达活性增强,而对NAA 没有明显的反应。看来某些外源植物激素对T-cyt启动子的活性有一定的诱导作用  相似文献   

3.
郭殿京  张晓东 《遗传学报》1999,26(2):168-173
将不同5上游调控序列驱动下的GUS基因用基因枪法导入小麦幼胚和胚性愈伤组织,通过组织化学分析法和荧光分析法对GUS基因的表达进行定量检测,比较了几种烟草花叶病毒(TMV)Ω增强子序列对小麦中外源基因瞬间表达的调控作用;然后将其中效率最高的玉米Ubil启动子与兔防御素(NP-1)连接起来,并加上Nos终止子,构民NP-1基因小麦表达载体,并转化小麦幼胚,经PCR-Suthern blot分析,初步确  相似文献   

4.
紫云英细胞转化条件的研究   总被引:2,自引:0,他引:2  
研究了紫云英(AstragalussinicusL.)细胞遗传转化的条件。根癌农杆菌(Agrobacteriumtum efaciens)经含乙酰丁香酮的低pH/PO3-4 诱导培养后,用来感染紫云英下胚轴原生质体,随后的细胞GUS瞬间表达活性显著提高,间接证明了上述预培养诱导活化了细菌vir基因,促进了T-DNA 向植物细胞转移。在PEG介导的DNA 转移中,较高的pH 和Ca2+ 浓度能够提高细胞GUS活性。质粒DNA 浓度及启动子类型对外源基因在植物细胞内表达也有一定影响。采用外植体-农杆菌共培养法,获得GUS和NPT Ⅱ基因稳定表达的紫云英转化植株  相似文献   

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芸苔属青菜(Brassica chinensis)与紫菜苔(B. cam pestrisvar. purpurea)的花粉经低温水合、热激、渗激三步程序,分离出大量具萌发能力的脱外壁花粉,脱外壁率可高达60% 以上。在含有碳源与氮源及Roberts培养基盐成分的碱性PEG 培养基中,首次使芸苔属脱外壁花粉萌发,萌发率可达33% ~41% 。在扫描电镜下观察了花粉脱外壁与萌发的过程。讨论了不同植物花粉脱外壁的方法与花粉壁生物学特点的对应关系,以及外壁对花粉萌发的可能作用  相似文献   

6.
日本Hiroshima大学和Kagawa大学的M.Nishihara和H.Morikawa及其同事报道,他们从用粒子轰击法转化的花粉第一次获得了稳定的转基因单倍体植株。Nishihara等人用含有新霉素转移酶Ⅱ(NPTⅡ)和β-葡糖苷酸酶(GUS)基因的质粒DNA包被的金粒,转化烟草属Nicotianarusticana的未成熟花粉。从被轰击的花粉再生了卡那霉素抗性花粉胚胎,并从总数为2×106个被轰击细胞中获得两个独立的转基因株系。一个同时具有NPTⅡ和GUS活性,另一个只有NPTⅡ活性。两个…  相似文献   

7.
日本血吸虫26kD抗原基因在BCG中的表达   总被引:5,自引:0,他引:5  
研究了外源基因日本血吸虫26kD抗原(Sj26GST)在卡介苗(bacilusCalmete-Guerin,BCG)、耻垢分枝杆菌(M.smegmatis)和大肠杆菌(E.coli)中的表达.运用重组DNA和聚合酶链反应(PCR)等分子生物学技术,以表达Sj26GST的E.colipGEX衍生质粒为模板,经PCR得到编码Sj26GST的全长cDNA片段.将其按正确的阅读框顺序,克隆到人结核杆菌热休克蛋白(heatshockprotein,HSP)70的启动子下游,再将HSP70启动子和Sj26GST基因一起亚克隆到E.coli-分枝杆菌穿梭质粒pBCG-2000中,得到E.coli-分枝杆菌穿梭表达质粒pBCG-Sj26.pBCG-Sj26电转化入BCG和M.smegmatismc2155中表达Sj26GST抗原,所表达的天然重组Sj26GST(rSj26GST)为可溶性蛋白,在SDS-PAGE上分子量为26kD处可见明显的表达蛋白带.其表达量分别占BCG和M.smegmatis菌体总蛋白的15%和10%.可见,Sj26GST基因能在BCG中高效表达.  相似文献   

8.
利用同源重组提高外源GUS基因在植物组织中表达   总被引:1,自引:0,他引:1  
将18S rRNA基因的部分片段,或烟草的核骨架结合序列(SARs)作为同源序列与外源GUS基因作为报告基因构建成用于基因打靶载体,以枪或农杆菌介导转化到拟南芥的根组织中,检测GUS基因瞬间表达的结果显示,两种同源基因序列均可提外源GUS基因的表达。  相似文献   

9.
马铃薯GBSS基因5‘侧翼区调控作用的研究   总被引:4,自引:0,他引:4  
将0.4、0.8、1.6、2.9kbGBSS基因的5'侧翼区与GUS基因融合,构建了双元表达载体。0.8kbGBSS-GUS通过基因枪介导在块茎切片中获得了瞬间表达。以上建构物通过农杆菌介导转入了马铃薯。X-Gluc染色及PCR结果证实已获得转基因植株。利用离体块茎诱导系统,GUS表达用荧光进行定量检测,结果显示,2.9、1.6、0.4kbGBSS-GUS的表达均以块茎明显高于茎段,达2 ̄10倍。  相似文献   

10.
本文通过聚合酶链式反应(PCR),从整合有人T细胞白血病病毒Ⅰ型(HTLV-I)的MT-2细胞株中,扩增出HTLV-I外膜蛋白(env)的全基因(1.45kb),并成功地克隆入pUC19载体,构建成env基因克隆env/pUC19.利用原核高效表达载体pGEX-2T,在大肠杆菌中有效地表达了与谷胱甘肽S-转移酶(GST)融合的env羧基末端抗原的重组蛋白,融合基因的转录由tac启动子调控。SDS-PAGE结果表明,有一约52kD的目的蛋白带,表达量占菌体总蛋白的10%;WesterNblott及ELISA结果显示,表达产物能与HTLV-I多抗血清结合。本研究为研制HTLV-I的诊断试剂及进一步了解env的免疫学和生物学性质打下了基础。  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   

17.
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   

18.
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   

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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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