植物转基因研究进展

经对植物转基因研究的成果进行了初步分析，概述了目前转基因植株的实际应用，新性状的获得及植物转基因的常用方法，指出了当前研究中存在的一些问题，探讨了植物转基因研究未来的发展方向。     

转基因林木生态安全性评价研究现状

近年来林木基因工程育种技术日益成熟,而转基因林木生态安全性评价相对滞后,其中转基因林木基因漂移研究尚处于空白。花粉传播是转基因植物外源基因发生转移的主要途径。文章对转基因植物基因漂移、林木开花散粉规律的研究现状进行综述,讨论了目前转基因植物基因漂移研究中存在的问题和发展前景,以期为转基因林木生态安全性评价研究提供依据。     

转基因技术在竹类植物育种中的应用前景

综述了转基因技术的应用现状。结合我国竹类植物研究现状,探讨了转基因技术在竹类植物新品种培育中的应用前景。     

转基因植物与转基因技术的发展与未来

进入21世纪转基因技术及其发展状况备受世人的瞩目，本文就转基因植物的产生，转基因植物的推广应用现状，世界各国对转基因研究的态度以及转基因技术的发展与未来作了较为全面的介绍与论述。     

转基因植物的安全性与合理利用

转基因植物向环境释放后町能带来的生态风险越来越受到人们的重视，生物安全性问题成为阻碍转基因植物大面积推广的主要因素。本文介绍了转基因植物安全性提出的必然，以及转基因植物释放后对植物本身和生态环境有可能产生的问题，并对转基因植物的合理利用提出了相应的对策建议。     

抗生素在农杆菌介导植物转基因中的应用

农杆菌介导植物转基因中常用抗生素包括抑茵剂和选择剂两大类。两类抗生素的作用机理不同。抗生素通常抑制植株的再生，也有较多的研究结果证明抗生素促进外植体的生长与分化。除用于筛选转化体或筛选转基因成株外，选择剂还用于鉴定转基因植物种子纯度、对转基因植物后代进行遗传分析。重点综述了农杆菌介导植物转基因中常用抗生素的作用机理及选择剂应用范围与方法的新进展，并讨论了抗生素在植物转基因中的安全性问题及应用前景。     

真正抗盐碱的转基因植物

最近,加拿大科学家研究培育了一种转基因植物。这种植物能在盐碱性超过普通盐碱地２倍的环境下正常生长,而不致出现生命受阻现象。在相同立地条件下,它比普通植物生长势强过数倍。真正抗盐碱的转基因植物@佟永宏     

植物抗虫基因的研究进展

随着转基因植物商品化进程的不断加深 ,转基因植物的发展前景及潜在的问题也越来越引起人们的关注 ,现对植物抗虫基因工程研究的最新进展、存在的问题及对策进行介绍     

林木基因工程风险评估和安全管理现状

综述了国内外林木基因工程的研究发展以及国内外现有的对转基因植物的安全评估和管理概况,强调了对转基因林木的评估标准和管理措施应结合林木自身特点逐一进行,以减少其可能造成的基因污染为重点。对我国转基因林木生物安全的评估和管理提出了一些建设。     

杨树转基因研究进展及展望

杨树是重要的栽培树种,也是研究林木基因工程的重要模式植物。杨树转基因研究可以打破种属限制,具有高效性和专一性的特点,是对杨树进行遗传改良的重要手段。为了更好的进行该方面的工作,本文介绍了杨树转基因涉及到的抗虫、抗除草剂、木材材性改良、抗逆、抗病、激素调控、开花调控和植物修复等应用领域的研究进展及现状,分析了影响杨树农杆菌转化效率的主要因素,并探讨了杨树转基因研究存在的问题及发展方向,希望能为后期从事林木基因工程研究的科研工作者提供依据。     

Rate of transgene spread via long-distance seed dispersal in Pinus taeda

Ecological risk analysis for transgenic conifers is more complex compared to transgenic food crops. With added age and size, greater quantities of seed and pollen travel even farther via long-distance dispersal. Perennial reproduction in conifers means that the same plant disperses annually for one or more decades prior to harvest. Although complex, gene flow in transgenic trees will have adverse consequences only if the following conditions are met: (1) the inserted gene or DNA construct itself inflicts harm or (2) the DNA insertion event causes unintended or secondary effects on fitness traits. Here, transgene seed escape into less managed ecosystems was modeled across 5 and 50 generations using Pinus taeda, an indigenous US timber commodity species. The inserted DNA construct itself was assumed to exert no direct effects on fitness but rather caused secondary or unintended effects on one or more fitness traits. The deterministic population genetics model, based on one or two fitness components, predicted the transgene allele frequency for a single colony of escaped transgenic seedlings through time. The first scenario modeled commercial transgenic plantations. A transgene allele escaping from a 100-ha plantation spread rapidly through time even if it exerted slight, unintended secondary effects on viability and fecundity. The second scenario modeled the case of a 10-ha field trial surrounded by non-transgenic or wild-type forests. Here, transgene spread was slowed by dilution from non-transgenic sources.     

香石竹ACC氧化酶重复基因植物表达载体的构建及转基因植株的获得

香石竹ACC氧化酶基因从核NDA中克隆之后,将其首先构建成正义及反义的单拷贝植物表达载体,在此基础上又同向插入一个ACO基因片段,从而获得ACO的正义重复基因和反义重复基因植物表达载体,所得载体已通过酶切分析和PCR鉴定。将该表达载体导入根癌农杆菌LBA4404菌株,并转化香石竹品种Master、爱卡迪幼叶,经PCR检测和Southem杂交鉴定,获得了8株转化植珠。     

Hybrid aspen with a transgene for fungal manganese peroxidase is a potential contributor to phytoremediation of the environment contaminated with bisphenol A

To assess the possible utility of a fungal gene for manganese-dependent peroxidase (MnP) produced by a transgenic plant in phytoremediation, we transformed hybrid aspen with a chimeric gene for MnP. Our gene construct allowed expression of the gene for MnP in plants and relatively high MnP activity was detected in the hydroponic medium in which roots of plants that expressed the transgene had been cultured. Some of our transgenic plants were able to remove bisphenol A from the medium more efficiently than wild-type plants. Our results demonstrate that, without any modification of the coding sequence, a chimeric gene for fungal MnP can be expressed in a woody plant, with secretion of active MnP from roots into the rhizosphere. Our strategy suggests new options using woody plants for phytoremediation.     

杨树抗虫转基因研究现状和发展趋势

杨树以其自身的优势发展迅速,无论是在生态环境的建设还是工业原料方面都做出了巨大的贡献。但是,其最大的天敌——虫害往往使其蒙受严重损失,为解决这一问题,科研人员进行了一系列工作,抗虫转基因便是最理想的一种。综合杨树抗虫转基因的研究现状,本文综述了杨树基因工程中各种抗虫基因的类型、杀虫机理、实验研究及抗虫性。指出杨树抗虫基因工程研发的重要性,进一步探讨了其前景。     

增加林木的纤维素生产和转基因树的生长(英文)

纤维素是植物组成中的重要多聚物。纤维素也是重要的工业原料和可再生的能源物质。利用转基因技术可以降低林木中木质素含量并增加纤维素含量。木质素合成酶基因4-CL是一个重要的和木材再生有关的基因。在我们的研究中,将利用反义表达方法降低木质素含量,增加纤维素含量。研究包括:D4-CL基因的分离;转基因植物的生产;纤维素和木质素含量分析;中试。参69。     

Assessment of rhizospheric microorganisms of transgenic Populus tomentosa with cowpea trypsin inhibitor ( CpTI ) gene

To have a preliminary insight into biosafety of genetically transformed hybrid triploid poplars (Populus tomentosa × P. bolleana) × P. tomentosa with the cowpea trypsin inhibitor (CpTI) gene, two layers of rhizospheric soil (from 0 to 20 cm deep and from 20 to 40 cm deep, respectively) were collected for microorganism culture, counting assay and PCR analysis to assess the potential impact of transgenic poplars on non-target microorganism population and transgene dispersal. When the same soil layer of suspension stock solution was diluted at both 1:1 000 and 1:10 000 rates, there were no significant differences in bacterium colony numbers between the inoculation plates of both transgenic and non-transgenic poplars. The uniform results were revealed for both soil layer suspension solutions of identical poplars at both dilution rates except for non-transgenic poplars at 1:10000 dilution rates from the same type of soil. No significant variation in morphology of both Gram-positive and Gram-negative bacteria was observed under the microscope. The potential transgene dispersal from root exudates or fallen leaves to non-target microbes was repudiated by PCR analysis, in which no CpTI gene specific DNA band was amplified for 15 sites of transgenic rhizospheric soil samples. It can be concluded that transgenic poplar with the CpTI gene has no severe impact on rhizospheric microorganisms and is tentatively safe to surrounding soil micro-ecosystem. [Supported by the National Project in Transgenic Plant and Application (Grant No. J2002-2003)]     

Assessment of Rhizospheric Microorganisms of Transgenic Populus tomentosa with Cowpea Trypsin Inhibitor (CpTI) Gene

To have a preliminary insight into biosafety of genetically transformed hybrid triploid poplars (Populus tomentosa × P. bolleana) × P. tomentosa with the cowpea trypsin inhibitor (CpTI) gene, two layers of rhizospheric soil (from 0 to 20 cm deep and from 20 to 40 cm deep, respectively) were collected for microorganism culture, counting assay and PCR analysis to assess the poten-tial impact of transgenic poplars on non-target microorganism population and transgene dispersal. When the same soil layer of suspension stock solution was diluted at both 1:1 000 and 1:10 000 rates, there were no significant differences in bacterium colony numbers between the inoculation plates of both transgenic and non-transgenic poplars. The uniform results were revealed for both soil layer suspension solutions of identical poplars at both dilution rates except for non-transgenic poplars at 1:10 000 dilution rates from the same type of soil. No significant variation in morphology of both Gram-positive and Gram-negative bacteria was observed under the microscope. The potential transgene dispersal from root exudates or fallen leaves to non-target microbes was repudiated by PCR analysis, in which no CpTI gene specific DNA band was amplified for 15 sites of transgenic rhizospheric soil samples. It can be concluded that transgenic poplar with the CpTI gene has no severe impact on rhizospheric microorganisms and is tentatively safe to surrounding soil micro-ecosystem.     

杨树抗虫转基因研究进展

本文对杨树抗虫基因及其杀虫机理、导入方法、检测方法、国内杨树抗虫转基因研究状况及抗虫效果、对其它生物的影响、存在的安全问题进行了系统的综述。同时,针对转基因植物生态安全性问题提出了相关对策。     

Physiological responses of wild type and putrescine-overproducing transgenic cells of poplar to variations in the form and concentration of nitrogen in the medium

We determined: (a) the physiological consequences of overproduction of putrescine in transgenic poplar (Populus nigra x maximoviczii) cells expressing an ornithine decarboxylase transgene; and (b) effects of variation in nitrogen (N) concentration of the medium on cellular polyamine concentration in transgenic and non-transgenic cells. Cells grown in the presence of supplemental (to the normal concentrations of N sources in the growth medium) and reduced amounts of NH4NO3 and KNO3 were used to study effects on membrane permeability, mitochondrial respiratory activity, protein accumulation, growth rates and changes in cellular polyamine concentration. The N concentration of the MS medium was not a limiting factor for continued overproduction of putrescine in transgenic cells. However, continued supplies of NH4+ and NO3- were required to maintain homeostatic amounts of putrescine in both cell lines. The presence of high amounts of putrescine in transgenic cells had significant effects on the physiological parameters measured. Compared with non-transgenic cells, transgenic cells had greater plasma membrane permeability, less tolerance to NH4NO3, more tolerance to KNO3, and accumulated higher amounts of soluble protein.     

Over-expression of Tryptophan Decarboxylase Gene in Poplar and its Possible Role in Resistance Against Malacosoma disstria

Amines and their derivatives are known to influence insect behavior involved in feeding and reproduction. In order to examine the feasibility of improving the resistance of poplar to insect pests by the introduction of a plant-derived amine-generating transgene, explants from the hybrid poplar clone ‘INRA 717 1B4’ (P. tremula ×P. albo) were transformed with a Camptotheca acuminata tryptophan decarboxylase (TDC, EC 4.1.1.28) cDNA driven by the CaMV 35S promoter. The enzyme TDC catalyzes the decarboxylation of tryptophan to tryptamine, which, in addition to being a bioactive amine itself, is known to act as a precursor of various other indole derivatives. Putative transgenic lines were confirmed by PCR for the TDC1 gene sequence and by the expression analysis of the transgene mRNA and encoded protein. No visible phenotypic changes were associated with ectopic TDC1 expression. Chemical and radiotracer analyses of the transgenic plants revealed tryptamine accumulation as high as 4 mM in leaf tissue, and suggested that the tryptamine produced by ectopically expressed TDC was not further metabolized. Insect bioassays with the TDC transgenic plants showed that the tryptamine accumulation was consistently associated with adverse effects on feeding potential and physiology of Malacosoma disstria (forest tent caterpillar).