代谢组学在转基因作物非预期效应评价中的应用

外源基因的非预期效应可能形成新的代谢产物或改变代谢模式,也可能引起转基因作物的营养成分发生改变,甚至可能会产生一些新的有毒物质,是转基因食品安全性评价的重要内容之一。本文主要对近年来代谢组学技术在转基因作物非预期效应评价中的最新应用做了总结,并阐述了对该研究领域的预期,以期促进转基因食品安全性评价体系的发展和完善。     

转基因食品的是是非非

转基因食品是指利用基因工程（转基因技术在物种基因组中嵌入了（非同种）特定的外源基因的食品,包括转基因植物食品、转基因动物食品和转基因微生物食品。转基因作为一种新兴的生物技术手段,它的不成熟和不确定性,必然使得转基因食品的安全性成为人们关注的焦点。     

“转基因食品检测与研究”专题征稿

<正>转基因食品是指利用基因工程(转基因)技术在物种基因组中嵌入(非同种)特定的外源基因的食品,包括转基因植物食品、转基因动物食品和转基因微生物食品。转基因作为一种新兴的生物技术手段,它的不成熟和不确定性,使得转基因食品的安全性成为人们关注的焦点。鉴于此,本刊特别策划了"转基因食品检测与研究"专题,由中国农业科学院北京畜牧兽医研究所李奎教     

“转基因食品检测与研究”专题征稿

<正>转基因食品是指利用基因工程(转基因)技术在物种基因组中嵌入(非同种)特定的外源基因的食品,包括转基因植物食品、转基因动物食品和转基因微生物食品。转基因作为一种新兴的生物技术手段,它的不成熟和不确定性,使得转基因食品的安全性成为人们关注的焦点。鉴于此,本刊特别策划了"转基因食品检测与研究"专题,由中国农业科学院北京畜牧兽医研究所李奎教授担任专题主编,围绕转基因食品成分检测、转基因食品特性研究、转基因食品研究现状等或您认为本领域     

“转基因食品检测与研究”专题征稿

<正>转基因食品是指利用基因工程(转基因)技术在物种基因组中嵌入(非同种)特定的外源基因的食品,包括转基因植物食品、转基因动物食品和转基因微生物食品。转基因作为一种新兴的生物技术手段,它的不成熟和不确定性,使得转基因食品的安全性成为人们关注的焦点。鉴于此,本刊特别策划了"转基因食品检测与研究"专题,由中国农业科学院北京畜牧兽医研究所李奎教授担任专题主编,围绕转基因食品成分检测、转基因食品特性研究、转基因食品研究现状等或您认为本领域有意义的问题进行论述,计划在2014年8月份出版。     

转基因食用农产品的快速检测方法

商业化转基因农作物广泛种植,转基因农产品被大量用作食品和动物饲料。我国和全球大部分国家都实行转基因生物强制标识制度。转基因农产品的现场监督检测急需稳定可靠的快速检测手段。本文论述了主要的基因水平检测方法包括PCR、基因芯片、环介导等温扩增技术(loop-mediated isothermal amplification,LAMP)和蛋白质水平检测方法(蛋白质免疫印迹法、酶联免疫吸附法、胶体金免疫层析试纸条法)。通过比较分析上述各检测方法的优缺点,LAMP和胶体金试纸条法是当前最理想的现场快速检测方法。     

转基因大豆低密度基因芯片的检测方法研究

目的建立Roundup Ready转基因大豆（简称RRS）的基因芯片检测方法,探讨其在转基因大豆检测中的应用。方法根据大豆中所转入的外源基因,选择camv35s启动子、nos终止子和cp4epsps基因,以大豆内源基因lectin基因为内参照基因设计了引物和探针,并制备了核苷酸芯片;通过多重PCR对样品核酸进行扩增和荧光标记后,将PCR产物与芯片杂交,检测大豆样品中所含的外源基因,并评价方法的灵敏度。结果检测转基因含量不同的RRS标准参考物,结果显示：camv35s启动子、nos终止子、外源基因cp4epsps检测灵敏度均可达0．45％。结论本研究所建立的基因芯片检测方法有良好的灵敏度及可重复性,有助于实现转基因大豆的高通量、高灵敏的检测。     

转基因食品安全评价及展望

介绍了转基因食品的实验室操作步骤和外源基因在转基因动、植物上的表达方法，同时叙述了目前国内外在转基因食品方面所采用的先进的检测手段，探讨了人们对转基因食品的安全性评定及其现存的危害，最后展望了转基因食品的发展前景。     

无选择标记技术与转基因植物食品安全性

转基因技术已被公认为提高农作物产量、改良农产品品质的革命性技术.转基因食品已越来越多地进入人们的日常生活.目前植物转基因操作中广泛使用选择标记基因,如抗生素或除草剂抗性基因等来筛选转化子.虽然尚无研究表明选择标记基因会影响人类健康,但近年来人们对转基因植物安全性问题的担心日益严重.为了消除公众对选择标记基因引起的转基因植物安全性的顾虑以及向已转化的植物中重复叠加外源基因等问题,无选择标记技术应运而生.这种全新的安全性转基因技术有巨大的应用潜力.本文对6种主要的无标记转基因技术及其在转基因植物食品安全性控制领域的应用做一综述.     

转基因食品的安全性及其检测评价

转基因食品发展迅速,但其安全仍然是人们关注的焦点。目前,通常从生态安全、健康安全、伦理安全的角度评价转基因食品的安全,并据此制定国际评价标准。转基因食品的分析检测建立在蛋白质和基因水平上,蛋白检测主要基于免疫原理检测粗加工食品的转基因蛋白成分,基因检测则基于PCR检测食品是否含有目的基因。同时,一些新型食品检测技术也逐步应用于转基因食品的检测。     

The integrated risk assessment of transgenic rice Oryza sativa: A comparative proteomics approach

The identification of unintended effects resulting from genetic modification processes is an important but difficult aspect of evaluations of the biosafety of genetically modified organisms (GMOs). Non-targeted techniques offer considerable potential for improving the detection of unintended effects of genetic modification in crop plants. In this study, total seed protein expression patterns of two strains of transgenic rice (Bt rice and PEPC rice) were examined using a comparative proteomics approach with two-dimensional electrophoresis (2-DE), and differences determined comparing to each line’s non GM counterpart. The results indicated that some of the seed proteins from the two transgenic rice lines differed in their relative intensities. Twenty eight proteins were successfully identified with MALDI-TOF-MS, five of which were well-characterized and these were discussed. In summary, transgenic rice were found to differ in their protein contents from their non-GM counterparts, which might raise concerns regarding their potential risks for human health and ecology.     

Effects of an exogenous xylanase gene expression on the growth of transgenic rice and the expression level of endogenous xylanase inhibitor gene RIXI

BACKGROUND: Xylanases have attracted considerable interest in recent years owing to their various applications in industry and agriculture. The use of transgenic plants to produce xylanases is a less expensive alternative to biotechnological programmes. The aim of this study was to elucidate whether introducing a foreign xylanase gene ATX into rice had any adverse effect on plant growth and development. RESULTS: A recombinant xylanase gene ATX was introduced into rice variety Zhonghua 11 through Agrobacterium‐mediated transformation. The T₂ generation of transgenic rice was compared with the control (non‐transgenic plants). Exogenous xylanase gene ATX was expressed in rice, and all examined transgenic lines exhibited xylanase activity. The transgenic lines (T₂, ‘X1‐3’ and ‘X2‐5’) appeared to grow and develop normally. There were no differences in net photosynthetic rate between transgenic rice lines (‘X1‐3’ and ‘X2‐5’) and wild type (WT) rice plants at the heading/flowering stage. Xylanases are key enzymes in the degradation of plant cell walls. Cell wall composition analysis showed that that there were no changes in cell wall polysaccharides in the root apex but some alterations in leaves in transgenic rice plants. The results also showed that the expression of exogenous xylanase gene ATX in rice would increase the expression of endogenous xylanase inhibitor gene RIXI, which could play a role in plant defence. Thus the stress resistance of transgenic rice plants might be improved. CONCLUSION: Exogenous xylanase gene ATX could be successfully expressed in rice, and the exogenous protein had no apparent harmful effects on growth and development in transgenic rice plants. Copyright © 2012 Society of Chemical Industry     

The definition,source, manifestation and assessment of unintended effects in genetically modified plants

At present, there is consensus among many relevant international agencies that unintended effects should be paid particular attention in the process of edible safety assessment of genetically modified plants (GMPs) and their products, especially in regard to some long‐term and potential food safety issues. However, with respect to the current risk assessment of GMPs, serious dissension on the apprehension of unintended effects exists. The present paper interprets and systematically analyses this dissension in order to review development on the definition, source and manifestation of unintended effects in GMPs. First, differences in the various concepts of unintended effect are discussed and compared. Then the mechanisms whereby unintended effects may arise during GMP breeding are analysed and the main unexpected variation manifestations in GMPs are presented. With regard to the safety assessment of unintended effects in GMPs, the current evaluation strategy, detection methods and several assessment cases are expounded. In addition, the unique assessment standard for unintended effects in GMPs in China is outlined. Copyright © 2008 Society of Chemical Industry     

转基因作物中外源基因在体内代谢途径的研究进展

为研究转基因食品中外源基因发生水平转移和其它危害的可能性，从而揭示转基因食品的安全性，综述了外源基因在体内代谢的途径及影响因素，外源基因在消化系统中的代谢降解，外源基因的水平转移以及外源基因在体内代谢途径的研究方法。     

转基因植物及其产品的应用价值和安全风险展望

随着转基因工程的飞速发展和转基因作物的种植推广,转基因植物及其产品逐渐深入人们的生活。本文介绍了转基因植物及其产品的应用价值和安全风险,从备受争议的环境和食品安全角度进行阐述,转基因植物的种植可能导致基因漂流、自然生物种群变化、病毒异源重组等环境影响,还可能产生过敏源、转基因作物抗性等威胁人类健康的不利影响。此外本文列举了各个国家关于转基因植物安全管理的相关法律法规,从安全风险监管角度出发,介绍了转基因食品的检测方法,并对转基因植物及其产品的安全风险管理提出了建议。     

fps转基因烤烟类胡萝卜素及其降解产物的研究

为探索法呢基焦磷酸合酶(fps)对烤烟中类胡萝卜素及其降解产物的影响,利用常规和GS/MS方法,对转fps基因烟草株系(K-4、K-6、K-17、K-35)烤后烟叶中类胡萝卜素含量及萜烯类香气物质含量进行了分析,结果发现,烤后烟叶类胡萝卜素含量有较大差异,与未转基因对照相比普遍有所提高,其中K-35含量最高;8种类胡萝卜素降解产物及茄酮、新植二烯含量有不同程度的提高,其中K-35香气降解产物含量整体较高,表明外源fps基因在烟草中的表达对类胡萝卜素合成具有促进作用,从而有利于烟叶品质的提高。     

叶片衰老诱导FLP重组酶删除转基因烟草外源基因的研究

  目的   “Gene-deletor”系统可实现转基因植物中外源基因的清除。为了研究该系统在转基因烟草中对清除外源基因的作用并最终创制不含外源基因的烟草新种质。  方法   以含有“Gene-deletor”系统的转基因烟株为材料,分析外源筛合报告选融基因Bar::GUS、重组酶基因FLP在不同叶龄叶片中的表达水平,同时通过观察转基因烟草花粉中GUS蛋白的表达活性,分析外源基因GUS在花粉中的删除情况。  结果   （1）相同叶龄不同转基因烟株叶片均表现出GUS活性和对除草剂草铵膦抗性,且3个转基因烟草株系中GUS活性和对除草剂抗性都表现出随着叶龄增大而降低的特点。（2）Real-time PCR和RT-PCR结果进一步证明外源Bar::GUS基因表达水平随叶片发育成熟持续下降,而外源FLP基因的表达水平则出现先增后降的变化趋势,在测定后期两者的表达量均达到最低,（3）花粉GUS组织染色结果表明,“明,色结果降的变化趋势,特系统诱导各转基因植株中花粉外源基因清除效率不同,平均清除率分别78.3%,54.7%和75.2%。  结论   在转基因烟草中,叶片衰老特异表达基因SAG12基因启动子驱动“动启动子驱动达基因,平均清系统（LoxP/FRT）的表达不仅可引起转基因植株叶片中外源基因的特异性清除,还能诱导花粉中外源基因的删除,该技术可为进一步创制培育不含外源基因的烟草新种质提供参考。      

Genetically Modified Feeds in Poultry Diet: Safety,Performance, and Product Quality

Concerns have been expressed regarding the safety of using biotechnology derived feeds in diets of livestock animals and in regard to human consumption of products from species fed transgenic crops. As a consequence, a large number of poultry nutrition studies have been conducted to evaluate the wholesomeness of transgenic crops by examining performances of animals during growth or egg laying. Studies also evaluated whether foreign DNA and proteins could be detected in meat, egg, and tissue samples from broiler chickens and laying hens fed diets containing transgenic feeds. In all studies, the conclusions were in agreement that the transgenic crops provided comparable performance, carcass and egg yields, and meat and egg composition, when compared with conventional grains. Moreover, it was demonstrated that transgenic proteins and DNA present in livestock feeds are not detectable in food products derived from these animals, using the most sensitive detection methods available, confirming that they are rapidly degraded by normal digestive processes. The lack of significant differences were a result of the similarity in nutrient composition of the genetically modified feeds and lack of differences in intake and digestibility, while there were no evidences that the differences reported for performance response variables and carcass measurements between treatment groups were attributable to the presence of the transgenic gene and protein in the biotechnology derived plants. Results demonstrated that genetically modified feeds are substantially equivalent and they result as safe as existing conventional feeds.     

HAL1基因转化烟草提高烟叶含钾量研究

提取酿酒酵母总RNA进行RT-PCR反转录,根据HAL1基因(GeneID:856113)序列设计阅读框引物,对反转录产物进行PCR扩增,并进行全序列测定,构建筛选标记为带内含子的Km抗性基因的植物双元表达载体,经根癌农杆菌介导法将HAL1基因导入烟草品种龙江911和K326中,进行卡那霉素抗性筛选、GUS染色、目的基因扩增和HAL1基因mRNA荧光定量PCR检测,并对T1代各转化烟草材料烟叶含钾量进行化验分析。测序结果证实PCR扩增得到的DNA与酿酒酵母HAL1基因序列相同,获得抗卡那霉素、GUS阳性的转化植株12株。经PCR扩增检测证实HAL1基因已整合入转基因烟草的基因组,荧光定量PCR分析结果表明HAL1基因已在烟苗根系表达,烟叶含钾量化验结果证明HAL1基因可使烟叶含钾量提高30%。      

多聚半乳糖醛酸酶(PG)反义基因转化加工番茄

通过农杆菌(Agrobacterium tumefaciens)LBA4404介导将多聚半乳糖醛酸酶(PG)反义基因导入新疆加工番茄(代号:99-162混)。卡那霉素抗性筛选,获得移栽成活的10株再生植株,PCR和Southern blot检测表明,其中4株再生植株的染色体中有外源基因的插入。所得4株转基因加工番茄在基因转化处理当代表现不同;果实饱满有光泽;Northern杂交结果表明,转反义PG基因加工番茄果实外果皮PG基因表达水平比对照低。转基因植株的表型观察和分子检测结果相吻合。