Development and collaborative validation of an event-specific quantitative real-time PCR method for detection of genetically modified CC-2 maize.

As one of the developed genetically modified (GM) maize varieties in China, CC-2 has demonstrated promising commercial prospects during demonstration planting. The establishment of detection methods is a technical prerequisite for effective supervision and regulation of CC-2 maize. In this study, we have developed an event-specific quantification method that targets the junction region between the exogenous gene and the 5' flanking genomic DNA (gDNA) of CC-2.

The CRISPR/Cas System: A Customizable Toolbox for Molecular Detection.

Clustered regularly interspaced short palindromic repeats (CRISPR) and their associated proteins (Cas) are promising molecular diagnostic tools for rapidly and precisely elucidating the structure and function of genomes due to their high specificity, programmability, and multi-system compatibility in nucleic acid recognition. Multiple parameters limit the ability of a CRISPR/Cas system to detect DNA or RNA. Consequently, it must be used in conjunction with other nucleic acid amplification techniques or signal detection techniques, and the reaction components and reaction conditions should be modified and optimized to maximize the detection performance of the CRISPR/Cas system against various targets.

Establishment and Validation of Reference Genes of L. for Digital PCR Detection of Genetically Modified Canola.

As an effective tool for genetically modified organism (GMO) quantification in complex matrices, digital PCR (dPCR) has been widely used for the quantification of genetically modified (GM) canola events; however, little is known about the quantification of GM canola events using endogenous reference gene () characteristics by dPCR. To calculate and quantify the content of GM canola using endogenous reference gene () characteristics, the suitability of several ERGs of canola, such as cruciferin A (), acetyl-CoA carboxylase (), phosphoenolpyruvate carboxylase (), cruciferin storage (), oleoyl hydrolase (), and high-mobility-group protein I/Y (), was investigated by droplet dPCR. and were more specific and stable in copy number in the genome of L.

Establishment and Application of Ligation Reaction-Based Method for Quantifying MicroR-156b.

Microribonucleic acids (miRNAs) play significant roles in the regulation of biological processes and in responses to biotic or abiotic environmental stresses. Therefore, it is necessary to quantitatively detect miRNAs to understand these complicated biological regulation mechanisms. This study established an ultrasensitive and highly specific method for the quantitative detection of miRNAs using simple operations on the ground of the ligation reaction of ribonucleotide-modified deoxyribonucleic acid (DNA) probes.

Event-specific quantitative polymerase chain reaction methods for detection of double-herbicide-resistant genetically modified corn MON 87419 based on the 3'-junction of the insertion site.

MON 87419 was one of the new transgenic corn events developed in US with the trait of herbicide resistance to both dicamba and glyphosate. To monitor unintended release of genetically modified organism in the future, as well as to meet GM-labeling requirements, it is requisite to develop a reliable method for the detection and quantification of MON 87419, an event-specific primer pair was designed to amplify the 3'-junction site between the endogenous genome sequence and the transferred DNA of GM event MON 87419, amplicons of desired size were produced by qualitative polymerase chain reaction (PCR) assay. For the validation of this quantitative method, the mixed samples containing 10%, 1%, and 0.

Development and validation of a 48-target analytical method for high-throughput monitoring of genetically modified organisms.

The rapid increase in the number of genetically modified (GM) varieties has led to a demand for high-throughput methods to detect genetically modified organisms (GMOs). We describe a new dynamic array-based high throughput method to simultaneously detect 48 targets in 48 samples on a Fludigm system. The test targets included species-specific genes, common screening elements, most of the Chinese-approved GM events, and several unapproved events.

Development and application of loop-mediated isothermal amplification assays for rapid visual detection of cry2Ab and cry3A genes in genetically-modified crops.

The cry2Ab and cry3A genes are two of the most important insect-resistant exogenous genes and had been widely used in genetically-modified crops. To develop more effective alternatives for the quick identification of genetically-modified organisms (GMOs) containing these genes, a rapid and visual loop-mediated isothermal amplification (LAMP) method to detect the cry2Ab and cry3A genes is described in this study. The LAMP assay can be finished within 60 min at an isothermal condition of 63 °C.

Dramatic genotypic difference in, and effect of genetic crossing on, tissue culture-induced mobility of retrotransposon Tos17 in rice.

KEY MESSAGE : We show for the first time that intraspecific crossing may impact mobility of the prominent endogenous retrotransposon Tos17 under tissue culture conditions in rice. Tos17, an endogenous copia retrotransposon of rice, is transpositionally active in tissue culture. To study whether there exists fundamental genotypic difference in the tissue culture-induced mobility of Tos17, and if so, whether the difference is under genetic and/or epigenetic control, we conducted this investigation.

Spaceflight-induced genetic and epigenetic changes in the rice (Oryza sativa L.) genome are independent of each other.

An array of studies have reported that the spaceflight environment is mutagenic and may induce phenotypic and genetic changes in diverse organisms. We reported recently that in at least some plant species (e.g.

The spaceflight environment can induce transpositional activation of multiple endogenous transposable elements in a genotype-dependent manner in rice.

Spaceflight represents a unique environmental condition whereby dysregulated gene expression and genomic instability can be provoked. However, detailed molecular characterization of the nature of genetic changes induced by spaceflight is yet to be documented in a higher eukaryote. Transposable elements (TEs) are ubiquitous and have played a significant role in genome evolution.

Spaceflight induces both transient and heritable alterations in DNA methylation and gene expression in rice (Oryza sativa L.).

Spaceflight represents a complex environmental condition in which several interacting factors such as cosmic radiation, microgravity and space magnetic fields are involved, which may provoke stress responses and jeopardize genome integrity. Given the inherent property of epigenetic modifications to respond to intrinsic as well as external perturbations, it is conceivable that epigenetic markers like DNA methylation may undergo alterations in response to spaceflight. We report here that extensive alteration in both DNA methylation and gene expression occurred in rice plants subjected to a spaceflight, as revealed by a set of characterized sequences including 6 transposable elements (TEs) and 11 cellular genes.

In planta mobilization of mPing and its putative autonomous element Pong in rice by hydrostatic pressurization.

The miniature Ping (mPing) is a recently discovered endogenous miniature inverted repeat transposable element (MITE) in rice, which can be mobilized by tissue culture or irradiation. It is reported here that mPing, together with one of its putative transposase-encoding partners, Pong, was efficiently mobilized in somatic cells of intact rice plants of two distinct cultivars derived from germinating seeds subjected to high hydrostatic pressure, whereas the other autonomous element of mPing, Ping, remained static in the plants studied. mPing excision was detected in several plants of both cultivars in the treated generation (P0), which were selected based on their novel phenotypes.

Alterations in DNA methylation and genome structure in two rice mutant lines induced by high pressure.

By using high-pressure treatment, two mutant lines were obtained from a genetically stable japonica rice cultivar Bijing38. Genomic DNA of the mutant lines, together with the original line (Bijing38), was either undigested or digested by Hpa IIMsp I, and then subjected to molecular analysis using two markers, ISSR and RAPD. Results indicated that changes in the PCR amplification profiles of both markers are apparent in the two mutant lines compared with the original rice cultivar, suggesting that there had been both sequence changes and DNA methylation modifications in the mutant lines.

Isolation and characterization of a set of disease resistance-gene analogs (RGAs) from wild rice, Zizania latifolia Griseb. I. Introgression, copy number lability, sequence change, and DNA methylation alteration in several rice-Zizania introgression lines.

Eight resistance-gene analogs (RGAs) were isolated from wild rice, Zizania latifolia Griseb., by degenerate primers designed according to conserved motifs at or around the nucleotide-binding site (NBS) of known NBS-containing plant resistance genes. The 8 RGAs were classified into 6 distinct groups based on their deduced amino acid sequence similarity of 60% or greater.

Heritable alteration in DNA methylation pattern occurred specifically at mobile elements in rice plants following hydrostatic pressurization.

Intrinsic DNA methylation pattern is an integral component of the epigenetic network in many eukaryotes. Exploring the extent to which DNA methylation patterns can be altered under a specific condition is important for elucidating the biological functions of this epigenetic modification. This is of added significance in plants wherein the newly acquired methylation patterns can be inherited through organismal generations.

Mobilization of the active MITE transposons mPing and Pong in rice by introgression from wild rice (Zizania latifolia Griseb.).

Hybridization between different species plays an important role in plant genome evolution, as well as is a widely used approach for crop improvement. McClintock has predicted that plant wide hybridization constitutes a "genomic shock" whereby cryptic transposable elements may be activated. However, direct experimental evidence showing a causal relationship between plant wide hybridization and transposon mobilization has not yet been reported.