共查询到17条相似文献,搜索用时 62 毫秒
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选择标记基因广泛应用于植物转基因工程中,然而这些基于除草剂和抗生素类抗性选择标记基因的利用,在转基因筛选和鉴定完成后功能多余。当前转基因植物的标记基因及相关产物对环境污染和食用安全的潜在影响,已经引起了人们的广泛关注。随着转基因技术的不断发展和人们对转基因植物和食品安全性的关注,删除转基因植物中的选择标记基因非常重要。文章着重讨论了植物转基因过程中,选择标记基因的利用,删除选择标记基因的几种方法,包括共转化法、位点特异性重组、染色体内重组、转座子介导的重组、删除叶绿体转化中选择标记基因,以及无选择标记基因植株的直接再生等。同时,还对这些技术的发展作了展望。 相似文献
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植物遗传转化中,标记基因起着非常重要的作用。目前使用的抗性标记基因大多数是抗生素或除草剂抗性基因,其引发的转基因植物安全性问题越来越受重视。笔者综述了近年来发展的各种无选择标记转基因植物方法及其在转基因植物中的应用,主要有共转化法、位点特异性重组系统、转座子系统、同源重组法和多元自主转化载体系统。通过评述各种方法的优缺点,以期推动安全型转基因植物培育和转基因植物产业化进程。 相似文献
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在植物基因转移过程中,标记基因常被用于筛选转化细胞或组织,给转基因工作带来很大方便.但在获得转基因植物之后,筛选标记基因的表达往往对环境及植物体的生长发育产生不良影响,且不利于使用相同标记基因进行多重转化.因此,使转基因植物释放后不带选择标记基因,对从事转基因的工作人员及消费者来说都是极为重要的.本文在对几种去除标记基因的方法进行总结的基础上,对该技术未来的发展趋势进行了展望. 相似文献
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在植物基因转移过程中,筛选标记基因常被用于筛选转化细胞或组织,给转基因工作带来很大方便;但在获得转基因植物之后,筛选标记基因的表达往往对环境及植物体的生长发育产生不良影响,且不利于使用相同标记基因进行多重转化。为了消除这些弊端,一种全新的发展策略即获得无选择标记转基因植物应运而生。文章主要综述获得无选择标记转基因植物的方法。 相似文献
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Marker-free GFP transgenic tobacco plants were constructed based on Cre/lox site-specific recombination system. A GFP gene was introduced into the tobacco genome using the Bar gene as a linked selectable marker flanked by recombination sites in a directed orientation. The Bar gene expression box was subsequently excised from the plant genome by a strategy of Cre gene retransformation. After removal of the Cre-NPT Ⅱ locus by genetic segregation through self-cross, plants that incorporated only the GFP transgene were obtained. Transgenic tobacco plants mediated by Agrobacterium tumefaciens were obtained, which resisted herbicide Basta and GFP expressed well, then the Cre gene was subsequently introduced into 5 plants of them, respectively, by retransformation. The leaf disks from Cre transgenic plants were used to test the resistance to Basta on the medium with 8 mg L-1 of PPT. The results showed that few discs were able to regenerate normally, and the excision at 76-100% efficiency depended on individual retransformation events. Evidence for a precise recombination event was confirmed by cloning the nucleotides sequence surrounding the lox sites of the Basta sensitive plants. The result indicated that the excision event in the recombination sites was precise and conservative, without loss or alteration of any submarginal nucleotides of the recombination sites. Bar gene excised plants were selfpollinated to allow segregation of the GFP gene from the Cre-NPT Ⅱ locus. The progenies from self-pollinated plants were scored for Kan senstivity, then the segregation of GFP gene from Cre-NPT Ⅱ locus in the Kan senstive plants were confirmed by PCR analysis subsequently. Hence, constructing marker-free transgenic tobacco plants by Cre/lox sitespecific recombination system was reliable, and the strategy presented here should be applicable to other plants for the construction of marker-free transgenic plants as well. 相似文献
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随着转基因植物商业化,转基因植物的安全性,尤其是转基因植物中的抗性标记基因,受到了越来越多的关注,因为人们担心这些抗性标记基因能够潜在地流向杂草、微生物或相关的植物并产生超级杂草、超级微生物或使一些相关的植物产生意外的性状,从而引发食品或生态安全问题。尽管这些担忧尚未有明确的科学根据,但培育无抗性标记基因的工程植株或使用安全性标记基因无疑会提高转基因植物的生物安全性,并有助于公众对转基因植物的认同和接受。为此,近年来已发展了多种提高植物转基因安全性的策略,该文即对这几种策略进行了综述和评价。 相似文献
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转基因技术在观赏植物育种中的应用 总被引:7,自引:1,他引:7
观赏植物在传统育种上取得了巨大的成就 ,但也存在一定的局限性 ,因此 ,很多人开始把目光转向转基因育种 ,它具有传统育种无法比拟的优越性 .观赏植物常用的转基因方法包括农杆菌介导转化法、基因枪法、电击法、PEG介导转化法和花粉管通道法等 ,目前已有多种观赏植物建立了遗传转化体系 .培育色彩新奇、形态优美、抗性优良、花期延长的花卉新品种是观赏植物转基因育种的主要目标 ,转基因技术在观赏植物的遗传改良中发挥着重要的作用 ,并有着极为广阔的前景 相似文献
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玉米Bt转基因植株抗虫性鉴定研究初报 总被引:5,自引:2,他引:5
经室内喂虫和田间接种,鉴定了Mo17,478等4个常用自交及其与91-1-8杂交的抗虫转基因杂种F1的抗虫性。结果表明,不同转基因材料之间以及同一转基因材料的不同单株间抗虫性差异很大,有少量植株表现高度抗性,个别植株几乎没有抗性。 相似文献
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Genetic and agronomic traits stability of marker-free transgenic wheat plants generated from Agrobacterium-mediated co-transformation in T_2 and T_3 generations 下载免费PDF全文
Genetically modified wheat has not been commercially utilized in agriculture largely due to regulatory hurdles associated with traditional transformation methods. Development of marker-free transgenic wheat plants will help to facilitate biosafety evaluation and the eventual environmental release of transgenic wheat varieties. In this study, the marker-free transgenic wheat plants previously obtained by Agrobacterium-mediated co-transformation of double T-DNAs vector were identified by fluorescence in situ hybridization(FISH) in the T_1 generation, and their genetic stability and agronomic traits were analyzed in T_2 and T_3 generations. FISH analysis indicated that the transgene often integrated into a position at the distal region of wheat chromosomes. Furthermore, we show that the GUS transgene was stably inherited in the marker-free transgenic plants in T_1 to T_3 generations. No significant differences in agronomic traits or grain characteristics were observed in T_3 generation, with the exception of a small variation in spike length and grains per spike in a few lines. The selection marker of bar gene was not found in the transgenic plants through T_1 to T_3 generations. The results from this investigation lay a solid foundation for the potential application of the marker-free transgenic wheat plants achieved through the co-transformation of double T-DNAs vector by Agrobacterium in agriculture after biosafty evaluation. 相似文献