Plant Genetic Engineering Technology Research Articles

Genome-Wide Association Studies of Embryogenic Callus Induction Rate in Peanut (Arachis hypogaea L.).

The capability of embryogenic callus induction is a prerequisite for in vitro plant regeneration. However, embryogenic callus induction is strongly genotype-dependent, thus hindering the development of in vitro plant genetic engineering technology. In this study, to examine the genetic variation in embryogenic callus induction rate (CIR) in peanut (Arachis hypogaea L.) at the seventh, eighth, and ninth subcultures (T7, T8, and T9, respectively), we performed genome-wide association studies (GWAS) for CIR in a population of 353 peanut accessions. The coefficient of variation of CIR among the genotypes was high in the T7, T8, and T9 subcultures (33.06%, 34.18%, and 35.54%, respectively), and the average CIR ranged from 1.58 to 1.66. A total of 53 significant single-nucleotide polymorphisms (SNPs) were detected (based on the threshold value -log10(p) = 4.5). Among these SNPs, SNPB03-83801701 showed high phenotypic variance and neared a gene that encodes a peroxisomal ABC transporter 1. SNPA05-94095749, representing a nonsynonymous mutation, was located in the Arahy.MIX90M locus (encoding an auxin response factor 19 protein) at T8, which was associated with callus formation. These results provide guidance for future elucidation of the regulatory mechanism of embryogenic callus induction in peanut.

Strategies for Engineering Virus Resistance in Potato.

Potato (Solanum tuberosum L.) is an important vegetable crop that plays a pivotal role in the world, especially given its potential to feed the world population and to act as the major staple food in many developing countries. Every year, significant crop loss is caused by viral diseases due to a lack of effective agrochemical treatments, since only transmission by insect vectors can be combated with the use of insecticides, and this has been an important factor hindering potato production. With the rapid development of molecular biology and plant genetic engineering technology, transgenic approaches and non-transgenic techniques (RNA interference and CRISPR-cas9) have been effectively employed to improve potato protection against devastating viruses. Moreover, the availability of viral sequences, potato genome sequences, and host immune mechanisms has remarkably facilitated potato genetic engineering. In this study, we summarize the progress of antiviral strategies applied in potato through engineering either virus-derived or plant-derived genes. These recent molecular insights into engineering approaches provide the necessary framework to develop viral resistance in potato in order to provide durable and broad-spectrum protection against important viral diseases of solanaceous crops.

Technological lock-in in action: Appraisal and policy commitment in Argentina's seed sector

This paper uses novel empirical evidence to analyse critically the widely held view that genetic engineering technology played a pivotal role in explaining the rapid expansion and increase in productivity of soy production in Argentina over the period from 1995 to 2015. We estimate the relative contribution of different approaches to seed innovation on soy performance over that period. We show how previous analyses have ignored the performance gains from plant breeding or misattributed them to genetic engineering. In our disaggregated assessment, seed innovations based on breeding techniques provide just as plausible an explanation for the expansion and performance gains of soy production. We illustrate how policy support to the seed industry is consistent with and is justified by mainstream narratives about the central role played by plant genetic engineering technology, and how the asymmetries created by these policy responses are contributing to the crowding out of plant breeding. This evidence, in our view, illustrates an important cognitive mechanism of lock-in to what may be a sub-optimal technology.

In-Silico Study of Brassinosteroid Signaling Genes in Rice Provides Insight Into Mechanisms Which Regulate Their Expression.

Brassinosteroids (BRs) regulate a diverse spectrum of processes during plant growth and development and modulate plant physiology in response to environmental fluctuations and stress factors. Thus, the BR signaling regulators have the potential to be targeted for gene editing to optimize the architecture of plants and make them more resilient to environmental stress. Our understanding of the BR signaling mechanism in monocot crop species is limited compared to our knowledge of this process accumulated in the model dicot species - Arabidopsis thaliana. A deeper understanding of the BR signaling and response during plant growth and adaptation to continually changing environmental conditions will provide insight into mechanisms that govern the coordinated expression of the BR signaling genes in rice (Oryza sativa) which is a model for cereal crops. Therefore, in this study a comprehensive and detailed in silico analysis of promoter sequences of rice BR signaling genes was performed. Moreover, expression profiles of these genes during various developmental stages and reactions to several stress conditions were analyzed. Additionally, a model of interactions between the encoded proteins was also established. The obtained results revealed that promoters of the 39 BR signaling genes are involved in various regulatory mechanisms and interdependent processes that influence growth, development, and stress response in rice. Different transcription factor-binding sites and cis-regulatory elements in the gene promoters were identified which are involved in regulation of the genes’ expression during plant development and reactions to stress conditions. The in-silico analysis of BR signaling genes in O. sativa provides information about mechanisms which regulate the coordinated expression of these genes during rice development and in response to other phytohormones and environmental factors. Since rice is both an important crop and the model species for other cereals, this information may be important for understanding the regulatory mechanisms that modulate the BR signaling in monocot species. It can also provide new ways for the plant genetic engineering technology by providing novel potential targets, either cis-elements or transcriptional factors, to create elite genotypes with desirable traits.

Heterologous Expression of LiSEP3 from Oriental Lilium Hybrid 'Sorbonne' Promotes the Flowering of Arabidopsis thaliana L.

The MADS-box gene family has multiple molecular and biological functions in plants. Here, the LiSEP3 gene of the MADS-box gene family of' 'Sorbonne' was obtained by homologous cloning using the petals of the flowering stage of Lilium Oriental Hybrid 'Sorbonne.' The ORF full-length sequence is 729bp, encoding 242 amino acids. Bioinformatics analysis showed that the relative molecular weight of the LiSEP3 protein is 27.67 kD and the isoelectric point (pI) is 9.16. The prediction result of the gene positioning is transcription in its nucleus. Homologous alignment of amino acid sequences showed that the protein not only had typical MADS-box and K-box domains, but also contained two short and relatively conservative SEP motifs. The phylogenetic tree showed that the amino acid sequence encoded by the LiSEP3 gene had the closest relationship with SEP3 in monocotyledon plants such as Apostasia odorata. The results of real-time PCR showed that LiSEP3 gene was mainly expressed in petal. During flower development, the expression level of the LiSEP3 gene showed an overall trend of initially increasing and then decreasing. The flowering time of LiSEP3 transgenic Arabidopsis thaliana L. plants was earlier than that of wild-type Arabidopsis thaliana L. plants, compared with wild type, the number of rosette leaves is less. In the transgenic plants, the expression of flowering-associated AtSPL5 and AtGI genes was up-regulated, while the expression of AtSVP and AtFRI genes that inhibit flowering was down-regulated, which was consistent with the statistical results of the flowering time of LiSEP3 transgenic plants. Our results illustrate that the heterologous expression of SEP3 functional genes in the MADS-box family promoted the flowering period of transgenic plants of this hybrid. This research provides a theoretical basis for improving the flowering period of ornamental plants through plant genetic engineering technology and enhancing their economic and social values.

Plant-Based Vaccines: Antigen Design, Diversity, and Strategies for High Level Production.

Vaccines for human use have conventionally been developed by the production of (1) microbial pathogens in eggs or mammalian cells that are then inactivated, or (2) by the production of pathogen proteins in mammalian and insect cells that are purified for vaccine formulation, as well as, more recently, (3) by using RNA or DNA fragments from pathogens. Another approach for recombinant antigen production in the last three decades has been the use of plants as biofactories. Only have few plant-produced vaccines been evaluated in clinical trials to fight against diseases, of which COVID-19 vaccines are the most recent to be FDA approved. In silico tools have accelerated vaccine design, which, combined with transitory antigen expression in plants, has led to the testing of promising prototypes in pre-clinical and clinical trials. Therefore, this review deals with a description of immunoinformatic tools and plant genetic engineering technologies used for antigen design (virus-like particles (VLP), subunit vaccines, VLP chimeras) and the main strategies for high antigen production levels. These key topics for plant-made vaccine development are discussed and perspectives are provided.

Understanding Wheat Starch Metabolism in Properties, Environmental Stress Condition, and Molecular Approaches for Value-Added Utilization.

Wheat starch is one of the most important components in wheat grain and is extensively used as the main source in bread, noodles, and cookies. The wheat endosperm is composed of about 70% starch, so differences in the quality and quantity of starch affect the flour processing characteristics. Investigations on starch composition, structure, morphology, molecular markers, and transformations are providing new and efficient techniques that can improve the quality of bread wheat. Additionally, wheat starch composition and quality are varied due to genetics and environmental factors. Starch is more sensitive to heat and drought stress compared to storage proteins. These stresses also have a great influence on the grain filling period and anthesis, and, consequently, a negative effect on starch synthesis. Sucrose metabolizing and starch synthesis enzymes are suppressed under heat and drought stress during the grain filling period. Therefore, it is important to illustrate starch and sucrose mechanisms during plant responses in the grain filling period. In recent years, most of these quality traits have been investigated through genetic modification studies. This is an attractive approach to improve functional properties in wheat starch. The new information collected from hybrid and transgenic plants is expected to help develop novel starch for understanding wheat starch biosynthesis and commercial use. Wheat transformation research using plant genetic engineering technology is the main purpose of continuously controlling and analyzing the properties of wheat starch. The aim of this paper is to review the structure, biosynthesis mechanism, quality, and response to heat and drought stress of wheat starch. Additionally, molecular markers and transformation studies are reviewed to elucidate starch quality in wheat.

Identification and analysis of key genes involved in methyl salicylate biosynthesis in different birch species.

Species of the perennial woody plant genus Betula dominate subalpine forests and play a significant role in preserving biological diversity. In addition to their conventional benefits, birches synthesize a wide range of secondary metabolites having pharmacological significance. Methyl salicylate (MeSA) is one of these naturally occurring compounds constitutively produced by different birch species. MeSA is therapeutically important in human medicine for muscle injuries and joint pain. However, MeSA is now mainly produced synthetically due to a lack of information relating to MeSA biosynthesis and regulation. In this study, we performed a comprehensive bioinformatics analysis of two candidate genes mediating MeSA biosynthesis, SALICYLIC ACID METHYLTRANSFERASE (SAMT) and SALICYLIC ACID-BINDING PROTEIN 2 (SABP2), of high (B. lenta, B. alleghaniensis, B. medwediewii, and B. grossa) and low (B. pendula, B. utilis, B. alnoides, and B. nana) MeSA-producing birch species. Phylogenetic analyses of SAMT and SABP2 genes and homologous genes from other plant species confirmed their evolutionary relationships. Multiple sequence alignments of the amino acid revealed the occurrence of important residues for substrate specificity in SAMT and SABP2. The analysis of cis elements in different birches indicated a functional multiplicity of SAMT and SABP2 and provided insights into the regulation of both genes. We successfully developed six prominent single nucleotide substitution markers that were validated with 38 additional birch individuals to differentiate high and low MeSA-producing birch species. Relative tissue-specific expression analysis of SAMT in leaf and bark tissue of two high and two low MeSA-synthesizing birches revealed a high expression in the bark of both high MeSA-synthesizing birches. In contrast, SABP2 expression in tissues revealed indifferent levels of expression between species belonging to the two groups. The comparative expression and bioinformatics analyses provided vital information that could be used to apply plant genetic engineering technology in the mass production of organic MeSA.

Recent advances and safety issues of transgenic plant-derived vaccines.

Transgenic plant-derived vaccines comprise a new type of bioreactor that combines plant genetic engineering technology with an organism's immunological response. This combination can be considered as a bioreactor that is produced by introducing foreign genes into plants that elicit special immunogenicity when introduced into animals or human beings. In comparison with traditional vaccines, plant vaccines have some significant advantages, such as low cost, greater safety, and greater effectiveness. In a number of recent studies, antigen-specific proteins have been successfully expressed in various plant tissues and have even been tested in animals and human beings. Therefore, edible vaccines of transgenic plants have a bright future. This review begins with a discussion of the immune mechanism and expression systems for transgenic plant vaccines. Then, current advances in different transgenic plant vaccines will be analyzed, including vaccines against pathogenic viruses, bacteria, and eukaryotic parasites. In view of the low expression levels for antigens in plants, high-level expression strategies of foreign protein in transgenic plants are recommended. Finally, the existing safety problems in transgenic plant vaccines were put forward will be discussed along with a number of appropriate solutions that will hopefully lead to future clinical application of edible plant vaccines.

Profile of Robert B. Goldberg

Over the next 50 years, as Earth's population races toward 9 billion inhabitants, we will need to produce more food than we have produced since the advent of agriculture 10,000 years ago (1). This challenge, warns National Academy of Sciences member Robert Goldberg, is particularly daunting given the finite and shrinking amount of arable land on which food crops can be grown. Increasing the yields of crop plants is therefore critical. With that goal in mind, Goldberg, a professor of molecular, cell, and developmental biology at the University of California at Los Angeles, has devoted his career to understanding the processes that program the life cycle of plants, with a particular focus on the genes required to make a seed. He envisions harvesting this information to engineer crops that produce more seeds, bigger seeds, and seeds with enhanced nutritional content, which could significantly enhance our food supply because the majority of the calories that people consume worldwide are either directly or indirectly obtained from seeds. Bob Goldberg in his office. Bob Goldberg in the classroom teaching his class “Genetic Engineering in Medicine, Agriculture, and Law”. Since the early 1970s, Goldberg has kept pace with the rapid discovery, development, and application of plant genetic engineering technologies. His pioneering work may lead to solutions to some of the most pressing problems that our society faces. His findings have changed the face of agriculture by enabling the production of new hybrids, such as the widely grown canola plants that produce at least 30% more oil than their conventional inbred parents. And Ceres—the plant biotech company that Goldberg cofounded—promises to change the way we produce fuel and electricity. A career in science was not on the horizon for the young Goldberg, born in 1944 and raised in an idyllic suburb of Cleveland, Ohio. “I …

Translocation of cell-penetrating peptides and delivery of their cargoes in triticale microspores

Microspore culture is contributing significantly in the field of plant breeding for crop improvement in general and cereals, in particular. In the present study, we investigated the uptake of fluorescently labeled cell-penetrating peptides (CPP; Tat, Tat(2), M-Tat, peptide vascular endothelial-cadherin, transportan) in the freshly isolated triticale microspores (mid-late uninucleate stage). We demonstrated that Tat (RKKRRQRRR) and Tat(2) (RKKRRQRRRRKKRRQRRR) are able to efficiently transduce GUS enzyme (272 kDa) in its functional form in 5 and 14% of the microspores, respectively, in a noncovalent manner. Pep-1, a synthetic CPP, was able to transduce GUS enzyme in its active form in 31% of the microspores. The effect of various endocytic and macropinocytic inhibitors on Tat(2)-mediated GUS enzyme delivery was studied and revealed a preferred micropinocytosis entry. DNase I protection assay and confocal laser microscopy was carried out to recommend a ratio of 4:1 Tat(2)-linear plasmid DNA (pActGUS) in complex preparation for microspore transfection. We further show that Tat(2) can successfully deliver GUS gene in near to 2% triticale microspores. The negative control mutated Tat (M-Tat: AKKRRQRRR) failed to transducer the GUS protein and transfect the GUS gene in microspore nucleus. The ability of CPPs to deliver macromolecules (protein as well as linear plasmid DNA) noncovalently has been demonstrated in triticale isolated microspores. It further confirms potential applications of CPPs in developing simple, time saving, cost effective plant genetic engineering technologies.

Biotechnological Prospects for Engineering Insect-Resistant Plants

Insect-resistant crops have been one of the major successes of applying plant genetic engineering technology to agriculture; cotton ( Gossypium hirsutum ) resistant to lepidopteran larvae (caterpillars) and maize ( Zea mays ) resistant to both lepidopteran and coleopteran larvae (rootworms) have

Between myth and reality: genetically modified maize, an example of a sizeable scientific controversy

Maize is a major crop plant with essential agronomical interests and a model plant for genetic studies. With the development of plant genetic engineering technology, many transgenic strains of this monocotyledonous plant have been produced over the past decade. In particular, field-cultivated insect-resistant Bt-maize hybrids are at the centre of an intense debate between scientists and organizations recalcitrant to genetically modified organisms (GMOs). This debate, which addresses both safety and ethical aspects, has raised questions about the impact of genetically modified (GM) crops on the biodiversity of traditional landraces and on the environment. Here, we review some of the key points of maize genetic history as well as the methods used to stably transform this cereal. We describe the genetically engineered Bt-maizes available for field cultivation and we investigate the controversial reports on their impacts on non-target insects such as the monarch butterfly and on the flow of transgenes into Mexican maize landraces.