转基因植物药物的开发研究评述

基因工程的完善与发展为利用转基因植物作为生物反应器来开发与生物转基因植物药物提供了可靠的技术基础，目前已利用转基因植物作为反应器生产出了多种转基因植物药物，其中包括多种药品和疫苗，已有的转基因植物药物的临床实验及国内外的应用表明转基因植物药物安全是可靠的，随着表达效率和遗传稳定性的不断提高，转基因植物药物的开发研究将会在21世纪得到更大的发展。     

转基因蔬菜口服疫苗研究进展

本文介绍了转基因蔬菜口服疫苗的优点，转基因植物口服疫苗在动物和人体中的应用和存在的问题。     

转基因蔬菜口服疫苗

介绍了转基因蔬菜口服疫苗的优点，外源基因在植物中表达的基本方法和遗传机制以及转基因植物口服疫苗在动物和人体中的应用和存在的问题。     

利用转基因植物生产基因工程疫苗

综述了10年来转基因植物疫苗的研究进展,分析了其中存在的问题,并提出了-些提高植物疫苗表达量的策略.     

H5N1型禽流感病毒HA基因在烟草中的表达

禽流感病毒H5N1是可以直接感染人类的甲型流感病毒，发展植物源口服疫苗是疫苗研究的方向之一．本研究通过农杆菌介导的方法将禽流感病毒H5N1的HA基因转化烟草．共获得38株潮霉素抗性植株，经PCR和Southern-blotting检测，目的基因已整合到转基因植株的基因组中．Western-dotting检测结果表明，目的基因在转基因烟草中得到表达，具有免疫原性，获得了能够表达HA基因的植物口服疫苗候选植株．     

基因工程疫苗的研究进展

随着分子生物学及重组DNA技术的发展,基因工程疫苗的研究不断深入,传统疫苗已体现出诸多缺陷,利用基因工程开发新疫苗是当前解决这个问题的最好途径之一.目前开发的主要有基因工程亚单位疫苗,基因工程活载体疫苗、核酸疫苗、合成肽疫苗、转基因植物可食疫苗、抗独特型疫苗等.本文对新型疫苗发展方向及进展情况作以综述.     

H5N1型禽流感病毒HA基因在烟草中的表达

禽流感病毒H5N1是可以直接感染人类的甲型流感病毒,发展植物源口服疫苗是疫苗研究的方向之一.本研究通过农杆菌介导的方法将禽流感病毒H5N1的HA基因转化烟草.共获得38株潮霉素抗性植株,经PCR和Southern-blotting检测,目的基因已整合到转基因植株的基因组中.Western-dotting检测结果表明,目的基因在转基因烟草中得到表达,具有免疫原性,获得了能够表达HA基因的植物口服疫苗候选植株.     

转基因植物的生态影响

自从1983年转基因植物诞生以来，至今各种类型的转基因植物进入大田实验已不计其数，很多产物已商品化。作为生物界的新品种，转基因植物在带来巨大的经济效益和社会效益的同时，也带来了潜在的风险。从生态学角度论述了转基因植物所带来的影响及采取相应的措施来加以调控和管理。     

转基因植物的安全性

随着现代生物技术的飞速发展，转基因食品得到了广大消费者的青睐。在目前已经被批准商业化生产的３ 类转基因食品中，植物转基因食品的重要性要比其它两类大得多，占 ９０％以上，因此，现阶段所说的转基因食品实际上主要是指转基因植物食品。 自１９８３年首次获得转基因植物以来，转基因技术发展十分迅速。１９９０ 年第一例转基因棉花田间种植试验成功。１９９６ 年至１９９９年共有１２个国家种植了转基因植物。目前已形成抗虫、抗病、抗逆、品质改良、控制发育和利用植物生产药物６ 大类转基因植物。根据美国农业部的统计，美国生产的…     

转基因植物研究进展

介绍了转基因植物的发展历史,已获得转基因植物的物种,转基因技术及转基因植物在生产上的应用.     

植物基因工程疫苗研究进展

可口服免疫(oral immunization)绿色疫苗(green vaccine)研究是植物基因工程与分子医学相结合而发展起来的新的研究方向．对当前植物基因工程疫苗的研究方法、疫苗的作用机理进行介绍,总结近10年来国内外植物基因工程疫苗研究进展,并对未来发展方向作出展望．     

结核疫苗研究进展

目的:回顾卡介苗(BCG)的应用情况,介绍关于结核疫苗研究进展的最新信息。方法:查阅大量关于结核疫苗研究的最近几年的文献。结果:有多种抗结核疫苗正在研究中,例如卡介苗、结核活疫苗、亚单位疫苗、DNA疫苗以及转基因植物疫苗等。结论:BCG仍是目前唯一可应用的抗结核疫苗,但是许多新疫苗己在动物模型中显示出潜力并开始进入临床试验。     

植物外源基因拷贝数及插入位点的检测方法与技术

随着转基因技术的快速发展,转基因植物在世界范围内已经大量种植.近年来,转基因植物的安全性越来越受到公众关注.转基因植物安全性与有效性的关键因素是外源基因拷贝数与插入位点.本文综述了近年来植物外源基因拷贝数与插入位点的检测方法.     

Resistance to rice blast (Pyricularia oryzae) caused by the expression of trichosanthin gene in transgenic rice plants transferred through agrobacterium method

The gene of trichosanthin has been transferred into rice plants through agrobacterium method. The single copy insertion and the expression of foreign gene have been proved in regenerated plants. In antifungal assay the degrees of rice blast (Pyricularia oryzae) infection of the transgenic plants expressing trichosanthin and expressingGUS gene as control have been evaluated. The differences such as the time of disease symptom observed, the number of infected plants and damaged leaves, the growth of infected plants of the two transgenic plants after being inoculated by rice blast (Pyricularia oryzae) are significant. The transgenic plants with trichosanthin gene grew faster than the plants withGUS gene, even when humidity environment was removed. The results show that the transgenic plants that expressed trichosanthin are able to delay the infection of rice blast compared with the plants as control. In addition, no damage caused by the expression of trichosanthin gene in transgenic plants has been observed.     

Overexpression of phospholipase <Emphasis Type="Italic">D</Emphasis>α gene enhances drought and salt tolerance of <Emphasis Type="Italic">Populus tomentosa</Emphasis>

The cDNA of AtPLDa （Arabidopsis thaliana Phospholipase Da） gene was introduced into P. tomentosa （Populus tomentosa） under the control of the Cauliflower mosaic virus 35S promoter. Southern and Northern blot analyses suggested that the AtPLDa gene has been transferred into the P. tomentosa genome. No obvious morphological or developmental difference was observed between the transgenic and wild-type （WT） plants. Drought and salt tolerance and gene expression of seedlings of several transgenic lines and WT plants （control） were studied. The results showed that the rhizogenesis rate and the average root-length of transgenic lines were significantly higher than WT plants after mannitol and NaCI treatment under the same growth conditions. Northern blot analysis indicated that the higher the PLDa expression in the transgenic plants, the more tolerant the transgenic plants are to drought and salt treatment. Meanwhile, another group of these transgenic lines and WT plants （control） were treated with PEG6000 and NaCI separately. The contents of chlorophylls and the activities of some anti- oxidant enzymes （superoxide dismutase, guaiacol peroxidase and catalase） as well as malondialdehyde and relative electrical conductivity were analyzed. Altogether, our results demonstrated that overexpression of the PLDa gene can enhance the drought and salt tolerance in transgenic P. tomentosa plants.     

Transgenic tobacco plants harboring tomato proteinase inhibitor II gene and their insect resistance

The plant expression vectors pBCT2 and pBT2 were constructed with the cDNA sequence (tin2) and genomic DNA sequence (tin2i) of tomato proteinase inhibitor II gene respectively. Then the two expression vectors were transferred into tobacco via the Agrobacterium tumefaciens strain LBA4404, and transgenic tobacco plants were generated. Molecular analysis and trypsin activity assay showed that both cDNA and genomic DNA were expressed properly in the transgenic plants. Insecticidal activities in these transgenic plants indicated that transgenic tobacco plants carrying tin2i sequence were more resistant to 2-instar larvae of Heliothis armigera Hubner than those carrying tin2 sequence. Therefore the intron of tin2i sequence might be a contributor to insecticidal activity of the transgenic tobacco.     

转基因小黑杨对土壤微生物群落结构的影响

为评价转基因林木环境释放可能引起的生态风险,以及转基因林木在生产应用中的可行性和可靠性,以实验室种植的转Bt-蜘蛛神经毒肽重组基因的小黑杨为材料,对转基因与非转基因植株根际(通常为几毫米至几厘米)土壤细菌、放线菌、真菌数量和基因水平转移情况进行检测,结果表明:转基因小黑杨种植一段时间后其根系附近的微生物数量略高于非转基因小黑杨。利用卡那霉素选择培养基分离根系周围细菌菌落发现转基因植株周围的土样细菌中,Kan^R抗性细菌菌落数占总细菌菌落的比例在11.58%～13.00%之间,而非转基因植株根际周围和空白土壤细菌菌落数则在5.73%～6.40%之间,表明转基因小黑杨根系对土壤细菌的抗生素抗性产生一定的影响。利用转基因植株的目的基因和抗性基因设计引物,以土壤中细菌基因组DNA为模板进行PCR扩增,转基因植株种植7个月后,根际土壤细菌菌落中含有抗性基因的菌落数量明显增加。虽然在种植1个月的转基因植株根际土壤土样细菌中未检出目的基因,但在种植7个月后的土样中检验到了很少的目的基因阳性细菌,阳性细菌菌落比例为2%～5%,检测结果表明可能有极少数Bt-蜘蛛神经毒肽重组基因发生了水平转移。     

拟南芥AtGluRS相互作用蛋白质VDAC及其转基因植物表型分析

电压依赖性阴离子通道蛋白质(voltage-dependent anion channel,VDAC)是拟南芥谷氨酰tRNA合成酶(AtGluRS)相互作用的蛋白质．为了研究VDAC蛋白的功能和作用,通过构建VDAC稳定表达载体,农杆菌介导的方法转化拟南芥,筛选和鉴定出VDAC过量和抑制表达植株．研究结果证实VDAC的过量和抑制表达植株影响气孔关闭和种子萌发．VDAC的过量表达导致植株对ABA敏感,VDAC的抑制表达降低了植株对ABA的敏感性．推测VDAC蛋白可能参与ABA信号途径．     

Transgenic tobacco plants expressing synthetic Cry1Ac and Cry1Ie genes are more toxic to cotton bollworm than those containing one gene

Transgenic tobacco plants carrying Cry1Ac, Cry1Ie or both genes were obtained. In the leaves of transgenic plants carrying both genes, the contents of Cry1Ac and Cry1Ie proteins were 0.173% and 0.131% of the total proteins, respectively. Cry1Ac protein content was 0.182% and Cry1Ie protein con- tent was 0.124% of the total proteins in the leaves of transgenic plants containing only one Bt gene. Fresh leaves of transgenic tobacco and wild-type plants were used for the insect bioassay against wild-type and Cry1Ac-resistant cotton bollworm (Helicoverpa armigera). The bioassay results showed that transgenic plants carrying both genes were significantly more toxic to wild-type and Cry1Ac-resistant cotton bollworm than those carrying Cry1Ac or Cry1Ie alone. This study indicates that the higher toxicity of transgenic tobacco plants carrying both genes is caused by the cooperative function of both Bt proteins, thus providing a potential way to delay the development of insect resis- tance to transgenic crops.