Construction of Multi-Specific Antibody by Genetic Engineering and Its Progress in Tumor Therapy

Targeted treatment of cancer with monoclonal antibodies increases the benefit for patients. In order to improve the anti-tumor activity of monoclonal antibodies, multi-specific antibodies have entered the research field. The emergence of various techniques to produce multi-specific recombinant antibody molecules has led to the selection of target combinations in various forms. To date, only a few multi-specific constructs have entered phase III clinical trials, in contrast to classical monoclonal antibodies. Some of the format options are outlined from a technical point of view. We focus on the achievements and prospects of the underlying technologies for generating biand multispecific antibodies.

Chloroplast Genetic Engineering in Higher Plants

Chloroplast genetic engineering, with several advantages over nuclear genetic engineering, is now regarded as an attractive new technology in basic and applied research, including deepening our understanding of plastid genome, engineering plant metabolic system, generating transplastomic plants with higher resistance to insect, disease, drought and herbicide and bioproducing of antibodies and vaccines. In this review, the principle and operating system for chloroplast genetic engineering and its application in higher plants have been discussed.

Advances in Cold Tolerance Genes and Their Application in Genetic Engineering of Plant for Cold Tolerance

Low temperature is one of the main environmental stress factors influenc- ing plant growth and development and crop yield. Cold tolerance genes and progress of their application in genetic engineering of plant for cold tolerance were reviewed comprehensively and systematically from the aspect of genes that are in- volved in biosynthesis of osmotic substances, genes coding fatty acid desaturation enzymes, antifreeze protein genes, genes coding antioxidant enzymes and so on, aiming at laying the foundation for genetic improvement of cold tolerance and breeding of plants.

Conifer genetic engineering: Particle bombardment and Agrobacterium-mediated gene transfer and its application in future forests

Many important advances in forest biotechnology have been made. The use of genetic transformation and the ap-plications of transgenic trees in modern forestry is now an important field. Two basic methodologies particle bombardment and Agrobacterium-mediated transformation have been used on conifers. However, routine procedures exist for only a limited number of conifers. As a result only a few species have been successfully transformed into stable transgenic plants. The use of a particle bombardment has been more successful and transgenic plants have been produced in Picea abies, Picea glauca, Picea mariana, and Pinus radiata, although the level of production of stable transgenic plants is lower than that of Agrobacte-rium. At present, breeding programs have been directed toward improving bole shape, growth rate, wood properties, and quality, as well as toward improving root and shoot performance, pest resistance, stress tolerance, herbicide resistance, and ability to resist stresses, which will drive forestry to enter a new era of productivity and quality. This article provides a brief overview of the current state of knowledge on genetic transformation in conifers.

Genetic engineering and lignin biosynthetic regulation in forest tree species

Genetic engineering of forest tree species is regarded as a strategy to reduce worldwide pressure on natural forests, to conserve genetic resources and ameliorate stress on global climate, and to meet growing demand for forest wood and timber products. Genetic engineering approaches toward the control or management of fungal pathogens, arthropod herbivores, bacterial and viral diseases, the use of pest resistance genes, and weed competitors are being studied. Although the production of transgenic trees is relatively recent and only a few species have been successfully genetically engineered in forest tree species, very useful and valuable information is available on the application of transgenic trees. Genes involved in important agricultural traits such as herbicide resistance, insect resistance, and wood quality have been isolated and have been used to genetically engineer trees. New technologies of plant molecular biology and genomics now make it possible high-efficient genetic improvement of forest trees. Genetic engineering promises to expand greatly the potential for genetic manipulation as new genes of commercial interest are discovered and utilized. Lignification is a process essential to the nature and evolution of vascular plants that is still poorly understood, even though it has been studied for more than a century. Recent studies on mutant and transgenic plants indicate that lignification may be far more flexible than previously realized. Rines with a mutation affecting the biosynthesis of the major lignin precursor, coniferyl alcohol, show a high level of an unusual subunit, dihydroconiferyl alcohol. It is also unusual as a plant polymer in that there are no plant enzymes for its degradation. These results have significant implications regarding the tradiational definition of lignin, and highlight the need for a better understanding of the lignin precursor biosynthetic pathway. In this review, we describe the progress made recently in genetic engineering of forest tree species.

Crop Resources Ethic in Plant Genetic Engineering and Fortune Transfer Between Generations

The relation between human and crop resources belongs to the ethic of resources exploitation. The purposes of discussing the ethic of crop resources are to protect the ecology and safety of crops, to gain sustainable development, furthermore, to choose and form the production structure that is favorable to saving crop resources and protecting the ecology of crops. Plant genetic engineering is the technology of molecule breeding of rearrangement of inheritance materials at the level of molecule directionally, of improving plant properties and of breeding high quality and yield varieties of crops. The prominent effects of the technology on the crop ecological system are human subjective factors increasing as well as violating the nature and intensifying the conflict between human being and nature. Therefore, in plant genetic engineering, crop resources exploitation should follow certain ethic principles. Under the theory of ethics of natural resources, by the means of biologinal-statistics, the author systematically analyzed the possible model of crop resources transfer between generations as well as the transfer mode of magnitude of real materials and magnitude of value.

A Review on Creating Male Sterility in Vegetable Crops by Genetic Engineering

With the deep researches on male sterility genetic engineering of plants, several strategies creating male sterile materials have been developed, such as causing pollen abortion by cytotoxic genes, antisense RNA or RNAi silencing the expression of genes related to pollen development, early degradation of tapetum callose leading to male sterility. Male sterile transgenic plants can be obtained through genetic transformation with related genes destroying or interfering with pollen or anther development. Male sterile cauliflower, tomato, cabbage, etc. have been developed in this way, and some begin to be used to produce hybrid seed. Appling some techniques can also maintain and restore the male sterility. These related researches will effectively promote the heterosis utilization and the development of crop breeding. This paper mainly presents their principles and applications in vegetable crops.

Recent advances in the molecular genetics of resin biosynthesis and genetic engineering strategies to improve defenses in conifers

Since the first terpenoid synthase cDNA was obtained by the reverse genetic approach from grand fir, great progress in the molecular genetics of terpenoid formation has been made with angiosperms and genes encoding a monoterpene synthase, a sesquiterpene synthase, and a diterpene synthase. Tree killing bark beetles and their vectored fungal pathogens are the most destructive agents of conifer forests worldwide. Conifers defend against attack by the constitutive and inducible production of oleoresin that accumulates at the wound site to kill invaders and both flush and seal the injury. Although toxic to the bark beetle and fungal pathogen, oleoresin also plays a central role in the chemical ecology of these boring insects. Recent advances in the molecular genetics of terpenoid biosynthesis provide evidence for the evolutionary origins of oleoresin and permit consideration of genetic engineering strategies to improve conifer defenses as a component of modern forest biotechnology. This review described enzymes of resin biosynthesis, structural feathers of genes genomic intron and exon organization, pathway organization and evolution, resin production and accumulation, interactions between conifer and bark beetle, and engineering strategies to improve conifer defenses.

Osmoregulation Mechanism of Drought Stress and Genetic Engineering Strategies for Improving Drought Resistance in Plants

Drought, one of the main adverse environmental factors, obviously affected plant growth and development. Many adaptive strategies have been developed in plants for coping with drought or water stress, among which osmoregulation is one of the important factors of plant drought tolerance. Many substances play important roles in plant osmoregulation for drought resistance, including proline, glycine betaine, Lea proteins and soluble sugars such as levan, trehalose, sucrose, etc. The osmoregulation mechanism and the genetic engineering of plant drought-tolerance are reviewed in this paper.

Editor's Choice——Application of genetic engineering for the treatment of neurodegenerative diseases

Gene therapy has been shown to be an effective method for protecting neural functions in the substantia nigra,

Preparation of Conotoxin MrVIB by Genetic Engineering Technology

[ Objective] The disulfide-rich conotoxin MrV1B was produced by simple and fast genetic engineering method, to find new efficient ways for the synthesis of natural active conotoxins. [Method] Primers of conotoxin gene MrVIB were synthesized to construct expression vectors pET22b（ ＋ ）/His-Xa-MrVIB and pET32a/Trx-EK-MrV1B, which were transformed into BL21 （DE3）pLysS and expressed under induction by IPTG. Recombinant proteins were purified by affinity chromatography using Ni-NTA agarose column, and the expression of the recombinant proteins was analyzed by Tricine-SDS-PAGE electrophoresis. [ Result] The recombinant conotoxins His-Xa-MrVIB and Trx-EK-MrVIB were effectively expressed in E. coli, and purified by one-step affinity chromatography, and the purity of the recombinant conotoxins was greater than 90%. [ Conclusion] The conotoxin MrVIB was effectively secreted and expressed by genetic engineering method, which could solve the problems in chemical synthesis of conotoxins including low yield, high cost and difficult purification.

Advantages and Disadvantages of Transgenic Animal Technology with Genetic Engineering

Transgenic animal technology has been one of the fastest growing biotechnology areas. The exogenous genes have been introduced into the animal genome by genetic engineering, so that these genes can be inherited and expressed by offspring to produce desired traits or evaluate function in elite livestock breeds. There are several methodologies for the production of transgenic animals, i.e., （1） microinjection of genes into pronuclei of fertilized ova; （2） DNA transfer by retroviruses; （3） injection of embryonic germ （EG）/embryonic stem （ES） cells previously treated with foreign DNA; （4） DNA transfer into cells and embryos with using liposomes; （5） exogenous DNA transfer while in vitro fertilization by using sperm; （6） electroporation of DNA into sperm, embryos or ova; （7） biolistics; （8） nuclear transfer （NT） with somatic cells, EG or ES cells; （9） germ line stem cell-mediated; （10） gene targeting; （! 1） gene silencing technology with RNA interference; （12） induced pluripotent stem cell; （13） zinc-finger nuclease gene targeting technology. Gene farming is one of the newest and most promising areas in modern biotechnology. Cattle, goats, sheep, pigs and rabbits are the main farm livestock species and fish is also used in transgenic technology. The question of ＂why make transgenic animals？＂ is very important. Some of the answers to this question are： （1） to obtain new knowledge; （2） to solve the genetic code; （3） to create genetic disease models; （4） to study the genetic control of physiological systems; （5） to improve animal production traits; （6） to produce new animal products. Transgenic technology is one of the main and important tools in the finding solutions to problems of growing population with their applications to different organisms, and takes more attention and interest every day. Transgenic technology creates opportunities and areas to play with organisms to fulfill the demands of people. Because of this, this paper based on mainly transgenic applications to take people＇s attention and exhibit its importance.

Approaches to Detecting Gene-Environment Interactions in Human Variation Using Genetic Engineering, Remote Sensing and GIS

Elucidation of the relationships between genetic polymorphisms and environmental exposures can provide insights into the pathways and mechanisms underlying complex traits. A new approach was used to detect G×E （gene-environment） interactions involved in human skin pigmentation variation to better understand the adaptive evolution of skin pigmentation. Specifically, we used genetic engineering, remote UVR （ultraviolet radiation） sensing and GIS （geographic information systems） to integrate the analysis of genetic and environmental factors into a coherent biological framework. Since we expected to generate large datasets for this multidimensional analysis, we used PCA （principal components analysis） as a spatial statistical analysis technique for analyzing the G×E interactions. The results suggest that skin pigmentation may be affected by mutations induced by UVR and support the hypothesis that global variation in skin pigmentation may be the result of localized adaptation to different UVR conditions via natural selection. Analyzing the relationships between heterozygous frequencies for SNP （single nucleotide polymorphism） loci and seasonal UVR levels as the environment changes will help elucidate the selective mechanisms involved in the UVR-induced evolution of skin pigmentation. Skin pigmentation fulfills the criteria for a successful evolutionary G×E interactions model.

Development Prospects of Genetic Engineering Pharmaceuticals

Human science and technology continue to advance over time.In the future,universal drugs will gradually fade out of our lives with the accumulation of time.With the advancement of genetic engineering,future genetic engineering drugs will be based on each difference and due to It differs from person to person,and the development of genetic engineering pharmaceuticals will make breakthroughs.

Human a Type Genetic Engineering Interference Essence Injection

The highest-level interference essence against virus and turnour genetic engineering medicine is a new type created in the 1980s. Compared with chemical medicines, the interference essence has a special effect in the treatment of viruses and tumours. The human a, type genetic engineering interference essense is prepared by the Institute of Viruses of the Chinese Academy of Preventive Medical Sciences, the Shanghai Vaccine

Genetic engineering drives the breakthrough of pig models in liver disease research

Compared with the widely used rodents,pigs are anatomically,physiologically,and genetically more similar to humans,making them high-quality models for the study of liver diseases.Here,we review the latest research progress on pigs as a model of human liver disease,including methods for establishing them and their advantages in studying cystic fibrosis liver disease,acute liver failure,liver regeneration,non-alcoholic fatty liver disease,liver tumors,and xenotransplantation.We also emphasize the importance of genetic engineering techniques,mainly the CRISPR/Cas9 system,which has greatly enhanced the utility of porcine models as a tool for substantially advancing liver disease research.Genetic engineering is expected to propel the pig as one of the irreplaceable animal models for future biomedical research.

Narrowing Down the Targets： Towards Successful Genetic Engineering of Drought-Tolerant Crops

Drought is the most important environmental stress affecting agriculture worldwide. Exploiting yield potential and maintaining yield stability of crops in water-limited environments are urgent tasks that must be undertaken in order to guarantee food supply for the increasing world population. Tremendous efforts have been devoted to identifying key regulators in plant drought response through genetic, molecular, and biochemical studies using, in most cases, the model species Arabidopsis thaliana. However, only a small portion of these regulators have been explored as potential candidate genes for their application in the improvement of drought tolerance in crops. Based on biological functions, these genes can be classified into the following three categories： （1） stress-responsive transcriptional regulation （e.g. DREB1, AREB, NF-YB）; （2） post-transcriptional RNA or protein modifications such as phosphorylation/dephosphorylation （e.g. SnRK2, ABI1） and farnesylation （e.g. ERA1）; and （3） osomoprotectant metabolism or molecular chaperones （e.g. CspB）. While continuing down the path to discovery of new target genes, serious efforts are also focused on fine-tuning the expression of the known candidate genes for stress tolerance in specific temporal and spatial patterns to avoid negative effects in plant growth and development. These efforts are starting to bear fruit by showing yield improvements in several crops under a variety of water-deprivation conditions. As most such evaluations have been performed under controlled growth environments, a gap still remains between early success in the laboratory and the application of these techniques to the elite cultivars of staple crops in the field. Nevertheless, significant progress has been made in the identification of signaling pathways and master regulators for drought tolerance. The knowledge acquired will facilitate the genetic engineering of single or multiple targets and quantitative trait loci in key crops to create commercialrade cultivars with high-yielding potential under both optimal and suboptimal conditions.

Hairy Root and Its Application in Plant Genetic Engineering

Agrobacterium rhizogenes Conn. causes hairy root disease In plants. Hairy root-Infected A. rhizogenes Is characterlzed by a high growth rate and genetic stability. Hairy root cultures have been proven to be an efficient means of producing secondary metabolites that are normally biosyntheslzed In roots of differentiated plants. Furthermore, a transgenlc root system offers tremendous potential for introducing additional genes along with the RI plasmld, especially with modified genes, into medicinal plant cells with A. rhizogenes vector systems. The cultures have turned out to be a valuable tool with which to study the biochemical properties and the gene expression profile of metabolic pathways. Moreover, the cultures can be used to elucidate the Intermediates and key enzymes Involved In the biosynthesis of secondary metabolites. The present article discusses various appllcations of hairy root cultures in plant genetic engineering and potential problems aseoclsted with them.

CRISPR ribonucleoprotein-mediated genetic engineering in plants

CRISPR-derived biotechnologies have revolutionized the genetic engineering field and have been widely applied in basic plant research and crop improvement.Commonly used Agrobacterium-or particle bombardment-mediated transformation approaches for the delivery of plasmid-encoded CRISPR reagents can result in the integration of exogenous recombinant DNA and potential off-target mutagenesis.Editing efficiency is also highly dependent on the design of the expression cassette and its genomic insertion site.Genetic engineering using CRISPR ribonucleoproteins(RNPs)has become an attractive approach with many advantages:DNA/transgene-free editing,minimal off-target effects,and reduced toxicity due to the rapid degradation of RNPs and the ability to titrate their dosage while maintaining high editing efficiency.Although RNP-mediated genetic engineering has been demonstrated in many plant species,its editing efficiency remains modest,and its application in many species is limited by difficulties in plant regeneration and selection.In this review,we summarize current developments and challenges in RNPmediated genetic engineering of plants and provide future research directions to broaden the use of this technology.