转基因动物技术及其研究进展

转基因动物技术是在基因工程、细胞工程和胚胎工程的基础上发展起来的,具有更广阔的应用前景,能应用于畜牧业、渔业和医疗领域中。综述了转基因动物技术概念、转基因动物技术研究现状,转基因动物技术导入外源基因的方法和步骤、转基因动物技术的应用以及转基因动物研究与应用存在的问题,并且对转基因动物技术在动物新品种培育、医学疾病模型研究和生物制药等领域的应用前景进行了展望。     

动物用转基因微生物安全性评价进展

转基因技术是将人工分离和修饰的外源基因导入生物体基因组中,这一技术的应用打破了异种微生物之间的天然屏障,从而使生物体获得了新的生物学性状。异种微生物间的天然的杂交屏障存在天然屏障,但是可以利用转基因生物技术打破,实现微生物间的基因转移、获得生物学性状不同的微生物。动物用转基因微生物与动物和人类的健康密切相关,也是公众最关心和最顾虑的转基因生物。其在给人类带来好处的同时,由于其生长繁殖快、变异类型多,向环境释放有不同的微生物或者因子,有可能对动物、微生物、人类及其生态环境带来不利影响或潜在的风险。本文就动物用转基因微生物的发展概况、安全性评价的原则,以及评价体系的进展进行了简要阐述。     

基因修饰技术及其在动物育种和生物医药领域的应用

基因修饰技术是一种能精确改造生物基因组,实现外源基因定点整合和基因定点敲除的技术。早期的基因修饰形式主要是转基因,随着科学研究的不断深入,新型基因修饰方法也逐渐研发出来,包括敲除、敲入、定点突变等。根据研究或应用的目的,可以将基因修饰技术分为转基因和基因敲除两方面内容。近年来,随着现代分子技术的高速发展,基因修饰技术不断改进创新,其相关方法和技术已逐步应用于改良家畜性状、研究基因功能、制作动物生物反应器以及构建人类疾病动物模型等领域中,使得畜禽基因功能的研究和转基因育种更加高效,在动物遗传育种以及生物医药等领域取得了显著成就,弥补了传统转基因技术的随机整合、遗传不稳定等缺陷,具有广阔的发展前景。作者从动物转基因和基因敲除技术两方面阐述了基因修饰技术的发展现状及发展趋势,并简要概括了基因修饰技术在动物育种和生物医药领域的应用现状。     

转基因动物的制备方法及应用评述

近些年来转基因技术在动物领域取得了很大进展,作者主要对转基因动物的制备方法及其优缺点进行了综述,指出了转基因动物在畜牧业、医药产业和人类疾病模型的建立等方面的应用及其存在的问题,最后就其未来的发展进行了展望。     

转基因猪的研究进展

随着转基因技术的不断发展,其在动植物领域都取得了很大的成果。本文综述了国内外转基因猪研究中常用的技术方法,转基因猪研究的概况及转基因猪应用的热点领域等。猪作为重要的经济动物是人类生活关系最为密切的家畜之一。因其妊娠期短,繁殖力很强,后代生长快等特点又使猪成为常用的实验研究动物。猪在解剖、组织、生理和营养代谢等方面均与人类最接近,因此,转基因猪吸引了众多科学家的极大热情,成功实例也证明了其在生命科学研究中具有独特的优越性和实用价值。     

转基因动物研究进展

近几年,转基因技术已成为生物界的研究热点,转基因动物作为一项生物高新技术成果,涉及到农牧业、生物医学和药物产业等诸多方面,显示出了广阔的应用前景与重要的经济价值.转基因技术对影响21世纪人类生存的重大环境、健康等问题的最终解决将发挥不可估量的作用,如改良动物经济性状提高经济效益、建立疾病动物模型从而加快人类疑难杂症的治愈、生产高价值的生物药品等.随着理论上和技术上的不断完善,转基因动物必将真正进入产业化和市场化,成为生产行业中的一种新兴产业.本文就转基因动物生产的方法、转基因动物的应用及存在的问题等作一综述,为该领域研究者提供参考.     

动物转基因技术在转基因牛中的研究进展及其应用

动物转基因技术已应用于生命科学的各个领域,特别是在研究基因功能、转基因动物培育、生物制药、提高畜禽的生产性能和防治疾病等方面得到了广泛应用。文章就动物转基因技术在转基因牛中的研究进展,以及在牛的基因功能研究、生物制药、防治疾病和改良品种等领域的应用和前景进行了综述,以期推进动物转基因技术在牛生产中的进一步发展。     

转基因技术提高动物生产性能的研究进展

动物转基因技术是在基因工程、细胞工程及胚胎工程的基础上发展起来的一种综合性的生物技术.利用该技术,人类可以按照自己意愿去改变动物的遗传组成,提高动物生长率,改进动物脂肪质量、动物乳品质量以及羊毛产量和品质,还可获得用于治疗或预防人类疾病的转基因生物药品等.然而,动物转基因技术仍在探索之中,许多问题尚未解决,转基因动物的...     

转基因技术在奶牛育种中的应用

转基因动物在现代生物技术领域中极其重要,目前已有转基因鼠、兔、猪、牛、鱼、鸡等多种转基因动物相继问世。文章论述了转基因技术的原理、技术方法以及转基因技术在奶牛育种中的应用,同时也指出了转基因动物存在的不足,展望了其发展前景。     

动物转基因技术研究新进展及其在牛育种上的应用

动物转基因技术已应用于生命科学的各个领域,尤其在研究基因功能、转基因动物育种（抗病育种和提高生产性能）、治疗人类疾病（生产药用蛋白、干细胞治疗和种器官移植）等方面得到了广泛的应用.本文从转基因技术的历史和发展状况入手,简要介绍了几种传统的转基因技术方法,重点综述了近几年为提高转基因效率和转基因精确调控的一些新技术.另外...     

Production of transgenic livestock: promise fulfilled

The introduction of specific genes into the genome of farm animals and its stable incorporation into the germ line has been a major technological advance in agriculture. Transgenic technology provides a method to rapidly introduce "new" genes into cattle, swine, sheep, and goats without crossbreeding. It is a more extreme methodology, but in essence, not really different from crossbreeding or genetic selection in its result. Methods to produce transgenic animals have been available for more than 20 yr, yet recently lines of transgenic livestock have been developed that have the potential to improve animal agriculture and benefit producers and/or consumers. There are a number of methods that can be used to produce transgenic animals. However, the primary method to date has been the microinjection of genes into the pronuclei of zygotes. This method is one of an array of rapidly developing transgenic methodologies. Another method that has enjoyed recent success is that of nuclear transfer or "cloning." The use of this technique to produce transgenic livestock will profoundly affect the use of transgenic technology in livestock production. Cell-based, nuclear transfer or cloning strategies have several distinct advantages for use in the production of transgenic livestock that cannot be attained using pronuclear injection of DNA. Practical applications of transgenesis in livestock production include enhanced prolificacy and reproductive performance, increased feed utilization and growth rate, improved carcass composition, improved milk production and/or composition, and increased disease resistance. One practical application of transgenics in swine production is to improve milk production and/or composition. To address the problem of low milk production, transgenic swine over-expressing the milk protein bovine alpha-lactalbumin were developed and characterized. The outcomes assessed were milk composition, milk yield, and piglet growth. Our results indicate that transgenic overexpression of milk proteins may provide a means to improve swine lactation performance.     

Use of Transgenic Animals to Improve Human Health and Animal Production

Contents Transgenic animals are more widely used for various purposes. Applications of animal transgenesis may be divided into three major categories: (i) to obtain information on gene function and regulation as well as on human diseases, (ii) to obtain high value products (recombinant pharmaceutical proteins and xeno-organs for humans) to be used for human therapy, and (iii) to improve animal products for human consumption. All these applications are directly or not related to human health. Animal transgenesis started in 1980. Important improvement of the methods has been made and are still being achieved to reduce cost as well as killing of animals and to improve the relevance of the models. This includes gene transfer and design of reliable vectors for transgene expression. This review describes the state of the art of animal transgenesis from a technical point of view. It also reports some of the applications in the medical field based on the use of transgenic animal models. The advance in the generation of pigs to be used as the source of organs for patients and in the preparation of pharmaceutical proteins from milk and other possible biological fluids from transgenic animals is described. The projects in course aiming at improving animal production by transgenesis are also depicted. Some the specific biosafety and bioethical problems raised by the different applications of transgenesis, including consumption of transgenic animal products are discussed.     

基因枪转化技术在动物转基因中应用的研究进展

基因枪转化技术无论在动物还是植物方面都产生了巨大的影响,因粒子介导的转基因方法简单、安全、高效,而越来越被人们所重视。研究结果表明,该转化技术不仅能够用于组织、细胞、器官,甚至可用于一些较难转染的靶目标,同时还可用于体内和体外信息的转换。目前手提式基因枪已广泛应用于皮肤、组织、各种细胞或内脏器官的转染,应用最广的领域是基因治疗,主要包括基因免疫和抑制肿瘤生长。近几年,基因枪技术发展迅速,应用范围越来越广,已经取得了丰硕的成果。作者主要叙述了基因枪转化的基本原理及近年来人们对基因枪转化技术条件的改进,同时就基因枪在动物转基因中的应用和一些主要的研究成果作了阐述,主要包括利用基因枪基因免疫、基因治疗、自杀基因治疗癌症、胚胎转基因、各种动物细胞和器官组织转基因等,并对基因枪技术在动物上应用的优势和不足进行了一些分析,最后展望了基因枪转化技术在动物中的应用前景。     

A brief overview of transgenic farm animals

Transgenesis offers new possibilities to rapidly modify the genome of living organisms. The application of transgenesis to farm animals faces many problems, more than those observed in the transgenesis of laboratory animals, as there are currently many different techniques available to obtain transgenic animals, which all have problems regarding low efficiency and high costs. When these techniques are applied to farm animals the problems concerning transgenesis are multiplied. Two main techniques, male pronuclear microinjection and sperm mediated gene transfer, utilised in farm animal transgenesis, are briefly presented. The improvement of these techniques and the employment of other biotechnologies such as cloning, could expand the uses of transgenic farm animals for human health.     

Manipulation of spermatogonial stem cells in livestock species

We are entering an exciting epoch in livestock biotechnology during which the fundamental approaches(such as transgenesis, spermatozoa cryopreservation and artificial insemination) will be enhanced based on the modern understanding of the biology of spermatogonial stem cells(SSCs) combined with the outstanding recent advances in genomic editing technologies and in vitro cell culture systems. The general aim of this review is to outline comprehensively the promising applications of SSC manipulation that could in the nearest future find practical application in livestock breeding. Here, we will focus on 1) the basics of mammalian SSC biology; 2) the approaches for SSC isolation and purification; 3) the available in vitro systems for the stable expansion of isolated SSCs; 4) a discussion of how the manipulation of SSCs can accelerate livestock transgenesis; 5) a thorough overview of the techniques of SSC transplantation in livestock species(including the preparation of recipients for SSC transplantation,the ultrasonographic-guided SSC transplantation technique in large farm animals, and the perspectives to improve further the SSC transplantation efficiency), and finally, 6) why SSC transplantation is valuable to extend the techniques of spermatozoa cryopreservation and/or artificial insemination. For situations where no reliable data have yet been obtained for a particular livestock species, we will rely on the data obtained from studies conducted in rodents because the knowledge gained from rodent research is translatable to livestock species to a great extent. On the other hand, we wil draw special attention to situations where such translation is not possible.     

CRISPR/Cas9技术在畜禽育种中的研究进展

利用传统方法在畜禽特定基因座上进行基因组修饰时,只能通过在体细胞中进行同源重组再经细胞核移植实现。传统同源重组方法的困难性和低效性阻碍了基因修饰在畜禽遗传育种中的广泛应用。近年来,位点特异性核酸内切酶的发现为靶向基因修饰提供了一条更直接的途径,主要由于这些酶能直接在DNA序列上进行一步式的基因编辑。成簇规律间隔短回文重复序列/Cas关联蛋白9(clustered regularly interspersed short palindromic repeat/CRISPR associated protein 9,CRISPR/Cas9)是一种RNA导向的DNA内切酶,精准定位于特定的靶位点,高效完成RNA导向的DNA识别及编辑。CRISPR/Cas9技术作为精准而强大的第3代基因组编辑工具,已经成功应用于猪、牛、山羊、绵羊和鸡上,这些CRISPR/Cas9基因编辑畜禽可作为研究人或畜禽生理和病理的生物模型、生产功能性蛋白质的生物反应器或器官移植的供体。特别是在畜禽生产方面,CRISPR/Cas9基因编辑可用于改善生产遗传特性及畜产品质量,提高畜禽对疾病的抵抗力。作者对当前畜禽中特定位点基因组修饰的CRISPR/Cas9技术的原理及基因组编辑在畜禽育种中应用的最新进展进行了综述,以期为推进CRISPR/Cas9技术在畜禽育种中的研究提供参考。     

Assisted reproductive techniques for cattle breeding in developing countries: a critical appraisal of their value and limitations

Commercialization of animal biotechnologies, including those related to reproduction [also known as assisted reproductive techniques (ARTS)], is an increasing reality in developing countries, following the enormous flow of information around us and the increasing global commercial interests in areas where cattle production has its major assets. The present review discusses the achievements of various biotechnological tools for reproduction in cattle including semen handling for artificial insemination (AI), superovulation and embryo transfer (MOET), in vitro handling of oocytes and production of embryos, reproductive cloning and emerging technologies (sex selection, gene targeting and nuclear transfer for livestock transgenesis, genomics for marker-assisted selection, etc.). The application of these technologies for cattle breeding is critically discussed in relation to their impact in the improvement of the efficiency of dairy and beef production in developed and - particularly - in developing countries, which ultimately rule the possibilities of a competitive and sound production of food for human consumption. Despite the remarkable progress made and the punctual importance of some of the above-mentioned technologies, AI remains the most important assisted reproductive technology (ART) in developing countries. Any attempt to gain widespread of any other ART under the predominant economical conditions in developing countries ought to match the simplicity and the success of AI as a breeding tool.     

mariner 转座子及其在昆虫种系转化中的应用

转座子是不需要同源重组便能在基因组内和基因组间移动的遗传学顺式元件.mariner是最简单的真核转座子,在昆虫中广泛分布.mariner转座子的转座作用只与转座酶有关,是一种很有发展前景的转基因载体,可以实现异源昆虫间的基因转移,产生稳定遗传的转基因品系.     

The role of genetic engineering in livestock production

In this paper we discuss the use of genetic engineering in livestock production. We examine the main two different aspects of genetic engineering: cloning and transgenesis. After commenting what has been expected from both techniques in livestock production in the last 25 years, the practical difficulties for implementing cloning and transgenesis are examined. Apart from technical difficulties, problems derived from the detection of genetically superior animals and evaluation of the clones and the transgenic animals make these techniques less interesting than they appear to be. Most of the observed variability of the economically interesting traits is not genetic, genetic evaluation needs a large number of animals and cloning success will represent a serious loss of genetic variability and the loss of the flexibility needed for markets in constant evolution. There is a risk in transgenic animals of production of new intermediate biochemical products that may be toxic, allergenic or carcinogenic. The benefits produced by transgenic animals hitherto hardly justify this risk. The expectations that genetic engineering produced 25 years ago should be re-examined, considering the risks and the high investment required.     

肌肉生长抑制素(MSTN)的研究进展

通过回顾前人的研究,综述了肌肉生长抑制素(MSTN)的发现、基础研究,以及近年来在人类和畜禽业中的研究进展,并探讨了MSTN基因的应用前景。