昆虫杆状病毒在生物技术研究中的应用

随着昆虫杆状病毒分子生物学研究的不断深入，昆虫杆状病毒在生物技术研究中也得到了应用。利用杆状病毒作为载体，在昆虫细胞和虫体内表达外源基因，形成了昆虫杆状病毒载体表达系统，利用杆状病毒携带外源基因，通过同源重组将外源基因导入到家蚕的基因组构建了转基因家蚕；通过向杆状病毒基因组中插入毒素、激素、酶抑制剂等的基因或从杆状病毒基因组中删除某个基因，或通过不同杆状病毒间的杂交，使子代病毒的宿主域扩大，从而提高了杆状病毒作为生物杀虫剂的杀虫效果。本文对杆状病毒在上述几个方面的应用进行了简要综述。     

Transgenic barley with overexpressed PTrx increases aluminum resistance in roots during germination

A transgenic barley line (LSY-11-1-1) with overexpressed Phalaris coerulescens thioredoxin gene (PTrx) was employed to measure the growth, protein oxidation, cell viability, and antioxidase activity in barley roots during germination on the presence of 2 mmol/L AlCl₃ on filter paper. The results show that (1) compared with the non-transgenic barley, LSY-11-1-1 had enhanced root growth, although both were seriously inhibited after AlCl₃ treatment; (2) the degree of protein oxidation and loss of cell viability in roots of LSY-11-1-1 were much less than those in roots of non-transgenic barley, as reflected by lower contents of protein carbonyl and Evans blue uptakes in LSY-11-1-1; (3) activities of catalase (CAT), glutathione peroxidase (GPX), ascorbate peroxidase (APX), and glutathione reductase (GR) in LSY-11-1-1 root tips were generally higher than those in non-transgenic barley root tips, although these antioxidase activities gave a rise to different degrees in both LSY-11-1-1 and non-transgenic barley under aluminum stress. These results indicate that overexpressing PTrx could efficiently protect barley roots from oxidative injury by increasing antioxidase activity, thereby quenching ROS caused by AlCl₃ during germination. These properties raise the possibility that transgenic barley with overexpressed PTrx may be used to reduce the aluminum toxicity in acid soils.     

百合转基因体系及分子育种相关基因的研究进展

通过分子育种的方法来改良百合品质以及开发新品种,是百合育种工作的热点之一.笔者在本文中对百合转基因体系建立的各种影响因素进行了探讨,综述了百合转基因分子育种中关注较多的报告基因、抗虫害基因、花发育相关基因等方面的现状及发展.     

Transient expression of chicken alpha interferon gene in lettuce

We investigated the possibility of producing chicken alpha interferon (ChIFN-α) in transgenic plants.The cDNA encoding ChIFN-a was introduced into lettuce (Lactuca sativa L.) plants by using an agro-infiltration transient expression system.The ChIFN-α gene was correctly transcribed and translated in the lettuce plants according to RT-PCR and ELISA assays.Re-combinant protein exhibited antiviral activity in vitro by inhibition of vesicular stomatitis virus (VSV) replication on chicken embryonic fibroblast (CEF).The results demonstrate that biologically active avian cytokine with potential pharmaceutical ap-plications could be expressed in transgenic lettuce plants and that it is possible to generate interferon protein in forage plants for preventing infectious diseases of poultry.     

MiR172介导的AP2-like转录因子表达对大岩桐花期调控的研究（英文）

目的:本文通过研究microRNA172a(miR172a)对成花途径中关键靶基因APETALA2类(AP2-like)的调控作用及其机理分析,探索通过操纵miRNA表达改变观赏植物花期的基因工程分子育种新策略。创新点:本研究基于植物miR172序列和功能的高度保守性,通过转基因的方法操纵大岩桐miR172的表达,进而影响AP2-like基因的表达,并起到调控花期的作用。方法:本研究借用拟南芥miR172a的已知序列构建组成型过表达载体35S:miR172a和抑制miR172表达的35S:MIM172载体。利用农杆菌介导法成功获得了35S:miR172a过表达株系以及抑制miR172作用的35S:MIM172株系,并利用cDNA末端快速扩增技术(rapid amplification of cDNA ends,RACE)克隆得到了大岩桐AP2-likecDNA全序列,并通过实时荧光定量聚合酶链式反应技术(qPCR)检测转基因株系中AP2-like的表达变化。结论:短日照条件下,35S:miR172a过表达株系花期比野生型提前(47.00±2.16)天;35S:MIM172株系花期延迟(7.00±4.28)天。在35S:miR172a过表达株系中miR172的表达水平明显上升,其靶基因SsAP2-like的表达量明显下降;35S:MIM172株系中miR172的积累水平受到抑制,而SsAP2-like的表达量明显上升,表明miR172介导调控SsAP2的表达对大岩桐成花转变具有促进作用。通过改变miR172的表达调控关键靶基因进而改变花期的方法可以作为调节观赏植物开花时间的有效策略。     

Science Letters: Transient expression of chicken alpha interferon gene in lettuce

We investigated the possibility of producing chicken alpha interferon (ChIFN-α) in transgenic plants.The cDNA encoding ChIFN-a was introduced into lettuce (Lactuca sativa L.) plants by using an agro-infiltration transient expression system.The ChIFN-α gene was correctly transcribed and translated in the lettuce plants according to RT-PCR and ELISA assays.Re-combinant protein exhibited antiviral activity in vitro by inhibition of vesicular stomatitis virus (VSV) replication on chicken embryonic fibroblast (CEF).The results demonstrate that biologically active avian cytokine with potential pharmaceutical ap-plications could be expressed in transgenic lettuce plants and that it is possible to generate interferon protein in forage plants for preventing infectious diseases of poultry.     

Expression of a begomoviral DNAβ gene in transgenic Nicotiana plants induced abnormal cell division

An increasing number of monopartite begomoviruses are being identified that a satellite molecule (DNAβ) is required to induce typical symptoms in host plants. DNAβ encodes a single gene (termed βC1) encoded in the complementary-sense. We have produced transgenic Nicotiana benthamiana and N. tabacum plants expressing theβC1 gene of a DNAβ associated with Tomato yellow leaf curl China virus (TYLCCNV), under the control of the Cauliflower mosaic virus 35S promoter. Transgenic plants expressing βC1 showed severe developmental abnormalities in both species. Microscopic analysis of sections of both transgenic and non-transgenic N. tabacum leaves showed abnormal outgrowths of transgenic N. tabacum to be due to disorganized cell division (hyperplasia) of spongy and palisade parenchyma. Immuno-gold labeling of sections with a polyclonal antibody against the βC1 protein showed that the βC1 protein accumulated in the nuclei of cells. The possible biological function of the βC1 protein was discussed.     

转基因生物产品及其安全性综述

生物技术的发展和应用,使得转基因食品进入了人类的食物链,由此也引发了转基因作物及产品的安全性争端.目前对此争端已逐渐达成共识.通过严格管理和科学检测、监控,发展转基因技术,将会为人类生活创造美好的未来.     

基因工程防治蚜虫研究进展

农作物的高产受到很多因素的影响,虫害就是其中非常重要的因素之一,全世界每年因此所遭受的损失高达近千亿美元.蚜虫是一种极为常见的农作物害虫,由于它宿主范围广泛,因而危害严重,如何有效地对它进行防治是许多科学工作者多年来一直致力研究的难题.近年来,由于生物技术的迅猛发展,利用基因工程方法选育抗蚜新品系的途径引起了人们的广泛关注.为此对近年来在抗蚜虫基因工程研究方面所取得的进展进行了综合评述.     

双引物PCR检测抗草甘膦豆粕饲料中的转基因成分

在一个PCR反应体系内,同步扩增大豆内参照基因lec和抗草甘膦大豆外源基因盒中的CaMV35s启动子、nos终止子或cp4 epsps基因,建立转基因大豆双引物PCR检测方法.PCR产物用限制性内切酶酶切进一步鉴定.结果表明,用双引物PCR扩增出标准转基因大豆阳性对照、阿根廷大豆、美国RR大豆及豆粕中的lec基因和相应的特异性外源基因;酶切反应确证PCR产物为特定片段大小的目的序列.建立的双引物PCR法适用于抗草甘膦大豆原料和豆粕饲料中转基因成分的简单化、高精度和高灵敏检测.