Response of rice to inoculation with genetic engineered strains of associative diazotrophs

Enhancement of nitrogen fixation in the rhizo-sphere of cereals has attracted a wide interestin biological and agricultural research,insteadof chemicals,for supplying higher plants withcombined nitrogen.Bacteria in association withrice plant.s were sensitive to the surroundingfactors in the soil,such as NH~+ or O,whichrepressed associative nitrogen fixation between

Plant biotechnology:a case study of Bacillus thuringiensis(Bt) and its application to the future of genetic engineered trees

Agricultural productivity may be raised in a sustainable way by many different technologies such as biological fertilizers, soil and water conservation, biodiversity conservation, improved pest control, and changes in land ownership and distribution. Of these measures, biotechnology applications probably hold the most promise in augmenting conventional agricultural productivity, because biotechnology applications give not only the need to increase production, but also protect the environment and conserving natural resources for future generations. Biotechnology applications will have the possibilities to increase productivity and food availability through better agronomic performance of new varieties, including resistance to pests; rapid multiplication of disease-free plants; ability to obtain natural plant products using tissue culture; diagnosis of diseases of plants and livestock; manipulation of reproduction methods increasing the efficiency of breeding; and the provision of incentives for greater participation by the private sector through investments. Insect resistance through the transfer of a gene for resistance fromBacillus thuringiensis (Bt) is one of the most advanced biotechnology applications already being commercialized in many parts of the world. This paper reviews the development and the status ofBt technology and application ofBt transgenic plants in current agriculture, and discusses specific issues related to the transfer of the technology to the future of genetic engineered trees with emphasis on conifers. Key words Agricultural productivity - Bacillus thuringiensis - Genetic engineering - Insect resistance - Trees CLC number Q812 - S763.306 Document code A Biography: Tang Wei (1964-), male, Ph. Doctor, Research associate, Department of Biology, Howell Science Complex, East Carelina University, Greenville, NC 27858-4353, USA.Responsible editor: Chal Ruihai

Optimization of Coenzyme Q10Production Procedure from Genetic Engineered Rhodobacter sphaeroides Overexpressing UbiG

In the present study, single factors including fermentation temperature, inoculate amount, fermentation duration, and ratio of fermentation medium volume to total flask volume(dissolved oxygen tension) were optimized for enhancing the production of coenzyme Q10 from genetic engineered Rhodobacter sphaeroides overexpressing UbiG. The experimental results suggested that optimal single factors were: inoculate amount 2%, fermentation temperature 30 ℃, fermentation duration 48 h, and ratio of fermentation medium volume to total flask volume 80%. The present study will promote the large scale production of CoQ10 from microorganisms.

Nonphytate Phosphorus Requirement and Efficacy of a Genetically Engineered Yeast Phytase for Yellow Broilers at 22- to 42-d-Old Age

An experiment was conducted to investigate the requirement of nonphytate phosphorus（nPP） and efficacy of a genetically engineered yeast phytase（PHY A） for Lingnan yellow broilers from 22-to 42-d-old age.A total of 1 320 1-d-old male chicks were randomly divided into 11 dietary treatment groups,which consisted of 4 replicate floor pens with 30 birds per pen.The control group（treatment 1） was fed with basal diet of nPP 0.08% without dicalcium phosphate or phytase supplementation.Dietary levels of nPP were 0.16,0.24,0.32,0.40,0.48,and 0.56%,respectively,for treatments 2 to 7,through addition of dicalcium phosphate（chemistry grade） to the basal diet.Diets of treatments 8 to 11 were supplemented with PHY A at 200,400 and 600 U kg-1,a commercial phytase product（PHY B） at 400 U kg-1 level,respectively.The birds in 0.32-0.56% nPP groups gained more than those of the other groups（P0.05）.The nPP supplementation significantly improved feed intake（P0.05）.The feed gain ratio was significantly decreased by 0.40% nPP diet compared to the control birds（P0.05）.The level of 0.48% nPP was required for optimum tibia development.The additions of PHY A at 400 and 600 U kg-1 level and PHY B all significantly improved ADG（P0.05）,ADFI（P0.05）,and dry defatted tibia weight（P0.05）.Similarly,the percentage of tibia ash was increased by 600 U kg-1 PHY A supplementation（P0.05）.The requirement of nPP for maximal ADG and highest percentage tibia ash both was 0.40%.The phosphorus equivalency value of PHY A was estimated as 685 U kg-1 for male yellow broilers of 22-to 42-d-old age.

Clinical trial perspective for adult and juvenile Huntington's disease using genetically-engineered mesenchymal stem cells

Progress to date from our group and others indicate that using genetically-engineered mesenchymal stem cells（MSC） to secrete brain-derived neurotrophic factor（BDNF） supports our plan to submit an Investigational New Drug application to the Food and Drug Administration for the future planned Phase 1 safety and tolerability trial of MSC/BDNF in patients with Huntington＇s disease（HD）. There are also potential applications of this approach beyond HD. Our biological delivery system for BDNF sets the precedent for adult stem cell therapy in the brain and could potentially be modified for other neurodegenerative disorders such as amyotrophic lateral sclerosis（ALS）, spinocerebellar ataxia（SCA）, Alzheimer＇s disease, and some forms of Parkinson＇s disease. The MSC/BDNF product could also be considered for studies of regeneration in traumatic brain injury, spinal cord and peripheral nerve injury. This work also provides a platform for our future gene editing studies, since we will again use MSCs to deliver the needed molecules into the central nervous system.

Biodegradation of azo dyes by genetically engineered azoreductase

A azoreductase gene with 537 bp was obtained by PCR amplification from Rhodobacter sphaeroides AS1 1737 The enzyme, with a molecular weight of 18 7 kD, was efficiently expressed in Escherichia coli and its biodegradation characteristics for azo dyes were investigated. Furthermore, the reaction kinetics and mechanism of azo dyes catalyzed by the genetically engineered azoreductase were studied in detail. The presence of a hydrazo-intermediate was identified, which provided a convincing evidence for the assumption that azo dyes were degraded via an incomplete reduction stage.

Genetically Engineered Corn Rootworm Resistance: Potential for Reduction of Human Health Effects From Pesticides

Objective and Methods Insecticide use, grower preferences regarding genetically engineered (GE) corn resistant to com rootworm (CRW), and the health effects of using various CRW insecticides (organophosphates, pyrethroids, fipronil and carbamates) are reviewed for current and future farm practices. Results Pest damage to corn has been reduced only one-third by insecticide applications. Health costs from insecticide use appear significant, but costs attributable to CRW control are not quantifiable from available data. Methods reducing health-related costs of insecticide-based CRW control should be evaluated. As a first step, organophosphate insecticide use has been reduced as they have high acute toxicity and risk of long-term neurological consequences. A second step is to use agents which more specifically target the CRW. Conclusion Whereas current insecticides may be poisonous to many species of insects, birds, mammals and humans, a protein derived from Bacillus thurigiensis and produced in plants via genetic modification can target the specific insect of CRW (Coleoptra), sparing other insect and non-insect species from injury.

“HoneySweet”Plum-A Valuable Genetically Engineered Fruit-Tree Cultivar

"HoneySweet" is a plum variety developed through genetic engineering to be highly resistant to plum pox potyvirus (PPV) the causal agent of sharka disease that threatens stone-fruit industries world-wide, and most specifically in Europe. Field testing for over 15 years in Europe has demonstrated the stable and durable PPV resistance of “HoneySweet”. Resistance is based on gene silencing whereby the inserted gene induces a natural plant defense mechanism against viruses. This resistance has been transferred to seedlings through cross-hybridization as a single locus dominant trait making it useful as a parent for developing new plum varieties for specific growing areas and markets. “HoneySweet” plums are of high quality and compare well to the quality and nutritional value of conventional plums. “HoneySweet” demonstrates the utilization of genetic engineering to provide safe and effective solutions to important agricultural challenges facing growers, and ultimately consumers.

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.

Overview of purple blotch disease and understanding its management through chemical, biological and genetic approaches

Purple blotch disease of Allium spp. crops caused by Alternaria porri has remained a major concern in agriculture for both farmers and research fraternity as it severely damages the crops and drastically reduces the yield. The symptoms appear after 1–4 days of infection and bulb rot begin, and eventually turn into dark reddish-purple and then brownish/black lesions. Many factors like season, time of sowing, humidity and temperature, stage of crop, and plant architecture have a huge impact on the progression of purple blotch disease. Many genic markers based on amplification of an Alta1 gene sequence have been designed for identification and differentiation of different Alternaria species groups. Among the most commonly used fungicides, mancozeb, tebuconazole, difenaconazole and azoxystrobin were found to be the ideal for the management of purple blotch disease and increased garlic yield. Many biological approaches such as plant extracts and bio-control agents were found partially effective for controlling the disease. A report on QTL mapping for purple blotch resistance discovered that purple blotch resistance is controlled by a single dominant gene ApR1. To completely understand the purple blotch disease resistance for crop improvement, a study is required at transcriptome level for hunting purple blotch resistant genes by gene annotation and mining. Genetic engineering and genome editing are other approaches that can be done for engineering disease resistance in Allium crops for genetic improvement.

Cell cycle exit and neuronal differentiation 1-engineered embryonic neural stem cells enhance neuronal differentiation and neurobehavioral recovery after experimental traumatic brain injury

Our previous study showed that cell cycle exit and neuronal differentiation 1(CEND1)may participate in neural stem cell cycle exit and oriented differentiation.However,whether CEND1-transfected neural stem cells can improve the prognosis of traumatic brain injury remained unclear.In this study,we performed quantitative proteomic analysis and found that after traumatic brain injury,CEND1 expression was downregulated in mouse brain tissue.Three days after traumatic brain injury,we transplanted CEND1-transfected neural stem cells into the area surrounding the injury site.We found that at 5 weeks after traumatic brain injury,transplantation of CEND1-transfected neural stem cells markedly alleviated brain atrophy and greatly improved neurological function.In vivo and in vitro results indicate that CEND1 overexpression inhibited the proliferation of neural stem cells,but significantly promoted their neuronal differentiation.Additionally,CEND1 overexpression reduced protein levels of Notch1 and cyclin D1,but increased levels of p21 in CEND1-transfected neural stem cells.Treatment with CEND1-transfected neural stem cells was superior to similar treatment without CEND1 transfection.These findings suggest that transplantation of CEND1-transfected neural stem cells is a promising cell therapy for traumatic brain injury.This study was approved by the Animal Ethics Committee of the School of Biomedical Engineering of Shanghai Jiao Tong University,China(approval No.2016034)on November 25,2016.

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.

Genes and genetics in eye diseases: a genomic medicine approach for investigating hereditary and inflammatory ocular disorders

Past 25 y have witnessed an exponential increase in knowledge and understanding of ocular diseases and their respective genetic underpinnings. As a result, scientists have mapped many genes and their variants that can influence vision and health of our eyes. Based on these findings, it is becoming clear that an early diagnosis employing genetic testing can help evaluate patients＇ conditions for instituting treatment plan（s） and follow-up care to avoid vision complications later. For example, knowing family history becomes crucial for inherited eye diseases as it can benefit members in family who may have similar eye diseases or predispositions. Therefore, gathering information from an elaborate examination along with complete assessment of past medical illness by ophthalmologists followed by consultation with geneticists can help create a roadmap for making diagnosis and treatment precise and beneficial. In this review, we present an update on ocular genomic medicine that we believe has tremendous potential towards unraveling genetic implications in ocular diseases and patients＇ susceptibilities. We also discuss translational aspects of genetic ophthalmology and genome engineering that may help advance molecular diagnostics and therapeutics.

Genetic Manipulation of Non-Classic Oilseed Plants for Enhancement of Their Potential as a Biofactory for Triacylglycerol Production

Global demand for vegetable oil is anticipated to double by 2030. The current vegetable oil production platforms, including oil palm and temperate oilseeds, are unlikely to produce such an expansion. Therefore, the exploration of novel vegetable oil sources has become increasingly important in order to make up this future vegetable oil shortfall. Triacylglycerol （TAG）, as the dominant form of vegetable oil, has recently attracted immense interest in terms of being produced in plant vegetative tissues via genetic engineering technologies. Multidiscipline-based ＂-omics＂ studies are increasingly enhancing our understanding of plant lipid biochemistry and metabolism. As a result, the identification of biochemical pathways and the annotation of key genes contributing to fatty acid biosynthesis and to lipid assembly and turnover have been effectively updated. In recent years, there has been a rapid development in the genetic enhancement of TAG accumulation in high-biomass plant vegetative tissues and oilseeds through the genetic manipulation of the key genes and regulators involved in TAG biosynthesis. In this review, current genetic engineering strategies ranging from single-gene manipulation to multigene stacking aimed at increasing plant biomass TAG accumulation are summarized. New directions and suggestions for plant oil production that may help to further alleviate the potential shortage of edible oil and biodiesel are discussed.

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.

Advancing approach and toolbox in optimization of chloroplast genetic transformation technology

Chloroplast is a discrete,highly structured,and semi-autonomous cellular organelle.The small genome of chloroplast makes it an up-and-coming platform for synthetic biology.As a special means of synthetic biology,chloroplast genetic engineering shows excellent potential in reconstructing various sophisticated metabolic pathways within the plants for specific purposes,such as improving crop photosynthetic capacity,enhancing plant stress resistance,and synthesizing new drugs and vaccines.However,many plant species exhibit limited efficiency or inability in chloroplast genetic transformation.Hence,new transformation technologies and tools are being constantly developed.In order to further expand and facilitate the application of chloroplast genetic engineering,this review summarizes the new technologies in chloroplast genetic transformation in recent years and discusses the choice of appropriate synthetic biological elements for the construction of efficient chloroplast transformation vectors.