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1.
Plant Physiol ; 187(3): 1481-1500, 2021 11 03.
Article in English | MEDLINE | ID: mdl-34618065

ABSTRACT

Sorghum (Sorghum bicolor) is a model C4 crop made experimentally tractable by extensive genomic and genetic resources. Biomass sorghum is studied as a feedstock for biofuel and forage. Mechanistic modeling suggests that reducing stomatal conductance (gs) could improve sorghum intrinsic water use efficiency (iWUE) and biomass production. Phenotyping to discover genotype-to-phenotype associations remains a bottleneck in understanding the mechanistic basis for natural variation in gs and iWUE. This study addressed multiple methodological limitations. Optical tomography and a machine learning tool were combined to measure stomatal density (SD). This was combined with rapid measurements of leaf photosynthetic gas exchange and specific leaf area (SLA). These traits were the subject of genome-wide association study and transcriptome-wide association study across 869 field-grown biomass sorghum accessions. The ratio of intracellular to ambient CO2 was genetically correlated with SD, SLA, gs, and biomass production. Plasticity in SD and SLA was interrelated with each other and with productivity across wet and dry growing seasons. Moderate-to-high heritability of traits studied across the large mapping population validated associations between DNA sequence variation or RNA transcript abundance and trait variation. A total of 394 unique genes underpinning variation in WUE-related traits are described with higher confidence because they were identified in multiple independent tests. This list was enriched in genes whose Arabidopsis (Arabidopsis thaliana) putative orthologs have functions related to stomatal or leaf development and leaf gas exchange, as well as genes with nonsynonymous/missense variants. These advances in methodology and knowledge will facilitate improving C4 crop WUE.


Subject(s)
Gene Expression Profiling , Genetic Techniques/instrumentation , Genome-Wide Association Study , Machine Learning , Sorghum/genetics , Water/metabolism , Life History Traits , Phenotype , Sorghum/metabolism
2.
Nat Methods ; 15(11): 921-923, 2018 11.
Article in English | MEDLINE | ID: mdl-30377360

ABSTRACT

FLIRT (fast local infrared thermogenetics) is a microscopy-based technology to locally and reversibly manipulate protein function while simultaneously monitoring the effects in vivo. FLIRT locally inactivates fast-acting temperature-sensitive mutant proteins. We demonstrate that FLIRT can control temperature-sensitive proteins required for cell division, Delta-Notch cell fate signaling, and germline structure in Caenorhabditis elegans with cell-specific and even subcellular precision.


Subject(s)
Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans/physiology , Genetic Techniques/instrumentation , Infrared Rays , Molecular Imaging/methods , Mutation , Temperature , Animals , Caenorhabditis elegans/genetics , Caenorhabditis elegans/radiation effects , Caenorhabditis elegans Proteins/genetics , Cell Differentiation , Embryo, Nonmammalian/cytology , Embryo, Nonmammalian/physiology , Gene Expression Regulation , Germ Cells , Microscopy , Receptors, Notch , Signal Transduction
3.
J Appl Microbiol ; 130(6): 1780-1793, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33128818

ABSTRACT

AIMS: We aimed to elucidate whether the DNA extraction kit and bacteria therein affect the characterization of bacterial communities associated with butterfly samples harbouring different bacterial abundancies. METHODS AND RESULTS: We analysed bacteria associated with eggs of Pieris brassicae and with adults of this butterfly, which were either untreated or treated with antibiotics (ABs). Three DNA extraction kits were used. Regardless of the extraction kit used, PCR amplification of the bacterial 16S rRNA gene detected very low bacterial presence in eggs and AB-treated butterflies. In untreated butterflies, bacterial signal intensity varied according to the kit and primers used. Sequencing (MiSeq) of the bacterial communities in untreated and AB-treated butterflies revealed a low alpha diversity in untreated butterflies because of the dominance of few bacteria genera, which were detectable regardless of the kit. However, a significantly greater alpha diversity was found in AB-treated butterflies, evidencing a true bias of the results due to bacterial contaminants in the kit. CONCLUSIONS: The so-called 'kitome' can impact the profiling of Lepidoptera-associated bacteria in samples with low bacterial biomass. SIGNIFICANCE AND IMPACT OF THE STUDY: Our study highlights the necessity of method testing and analysis of negative controls when investigating Lepidoptera-associated bacterial communities.


Subject(s)
Bacteria/isolation & purification , Butterflies/microbiology , DNA, Bacterial/isolation & purification , Genetic Techniques/instrumentation , Animals , Bacteria/classification , Bacteria/genetics , Biomass , DNA Primers , DNA, Bacterial/genetics , Microbiota/genetics , Polymerase Chain Reaction/methods , RNA, Ribosomal, 16S/genetics
4.
BMC Biol ; 18(1): 1, 2020 01 02.
Article in English | MEDLINE | ID: mdl-31898513

ABSTRACT

BACKGROUND: New sequencing technologies have lowered financial barriers to whole genome sequencing, but resulting assemblies are often fragmented and far from 'finished'. Updating multi-scaffold drafts to chromosome-level status can be achieved through experimental mapping or re-sequencing efforts. Avoiding the costs associated with such approaches, comparative genomic analysis of gene order conservation (synteny) to predict scaffold neighbours (adjacencies) offers a potentially useful complementary method for improving draft assemblies. RESULTS: We evaluated and employed 3 gene synteny-based methods applied to 21 Anopheles mosquito assemblies to produce consensus sets of scaffold adjacencies. For subsets of the assemblies, we integrated these with additional supporting data to confirm and complement the synteny-based adjacencies: 6 with physical mapping data that anchor scaffolds to chromosome locations, 13 with paired-end RNA sequencing (RNAseq) data, and 3 with new assemblies based on re-scaffolding or long-read data. Our combined analyses produced 20 new superscaffolded assemblies with improved contiguities: 7 for which assignments of non-anchored scaffolds to chromosome arms span more than 75% of the assemblies, and a further 7 with chromosome anchoring including an 88% anchored Anopheles arabiensis assembly and, respectively, 73% and 84% anchored assemblies with comprehensively updated cytogenetic photomaps for Anopheles funestus and Anopheles stephensi. CONCLUSIONS: Experimental data from probe mapping, RNAseq, or long-read technologies, where available, all contribute to successful upgrading of draft assemblies. Our evaluations show that gene synteny-based computational methods represent a valuable alternative or complementary approach. Our improved Anopheles reference assemblies highlight the utility of applying comparative genomics approaches to improve community genomic resources.


Subject(s)
Anopheles/genetics , Biological Evolution , Chromosomes , Genetic Techniques/instrumentation , Genomics/methods , Synteny , Animals , Chromosome Mapping
5.
Malar J ; 19(1): 181, 2020 May 13.
Article in English | MEDLINE | ID: mdl-32404110

ABSTRACT

BACKGROUND: Long regarded as an epicenter of drug-resistant malaria, Southeast Asia continues to provide new challenges to the control of Plasmodium falciparum malaria. Recently, resistance to the artemisinin combination therapy partner drug piperaquine has been observed in multiple locations across Southeast Asia. Genetic studies have identified single nucleotide polymorphisms as well as copy number variations in the plasmepsin 2 and plasmepsin 3 genes, which encode haemoglobin-degrading proteases that associate with clinical and in vitro piperaquine resistance. RESULTS: To accurately and quickly determine the presence of copy number variations in the plasmepsin 2/3 genes in field isolates, this study developed a quantitative PCR assay using TaqMan probes. Copy number estimates were validated using a separate SYBR green-based quantitative PCR assay as well as a novel PCR-based breakpoint assay to detect the hybrid gene product. Field samples from 2012 to 2015 across three sites in Cambodia were tested using DNA extracted from dried blood spots and whole blood to monitor the extent of plasmepsin 2/3 gene amplifications, as well as amplifications in the multidrug resistance transporter 1 gene (pfmdr1), a marker of mefloquine resistance. This study found high concordance across all methods of copy number detection. For samples derived from dried blood spots, a success rate greater than 80% was found in each assay, with more recent samples performing better. Evidence of extensive plasmepsin 2/3 copy number amplifications was observed in Pursat (94%, 2015) (Western Cambodia) and Preah Vihear (87%, 2014) (Northern Cambodia), and lower levels in Ratanakiri (16%, 2014) (Eastern Cambodia). A shift was observed from two copies of plasmepsin 2 in Pursat in 2013 to three copies in 2014-2015 (25% to 64%). Pfmdr1 amplifications were absent in all samples from Preah Vihear and Ratanakiri in 2014 and absent in Pursat in 2015. CONCLUSIONS: The multiplex TaqMan assay is a robust tool for monitoring both plasmepsin 2/3 and pfmdr1 copy number variations in field isolates, and the SYBR-green and breakpoint assays are useful for monitoring plasmepsin 2/3 amplifications. This study shows increasing levels of plasmepsin 2 copy numbers across Cambodia from 2012 to 2015 and a complete reversion of multicopy pfmdr1 parasites to single copy parasites in all study locations.


Subject(s)
Antimalarials/pharmacology , Aspartic Acid Endopeptidases/genetics , DNA Copy Number Variations/genetics , Drug Resistance/genetics , Genetic Techniques/instrumentation , Plasmodium falciparum/genetics , Quinolines/pharmacology
6.
Parasitology ; 146(11): 1361-1370, 2019 09.
Article in English | MEDLINE | ID: mdl-31142396

ABSTRACT

New technological methods, such as rapidly developing molecular approaches, often provide new tools for scientific advances. However, these new tools are often not utilized equally across different research areas, possibly leading to disparities in progress between these areas. Here, we use empirical evidence from the scientific literature to test for potential discrepancies in the use of genetic tools to study parasitic vs non-parasitic organisms across three distinguishable molecular periods, the allozyme, nucleotide and genomics periods. Publications on parasites constitute only a fraction (<5%) of the total research output across all molecular periods and are dominated by medically relevant parasites (especially protists), particularly during the early phase of each period. Our analysis suggests an increasing complexity of topics and research questions being addressed with the development of more sophisticated molecular tools, with the research focus between the periods shifting from predominantly species discovery to broader theory-focused questions. We conclude that both new and older molecular methods offer powerful tools for research on parasites, including their diverse roles in ecosystems and their relevance as human pathogens. While older methods, such as barcoding approaches, will continue to feature in the molecular toolbox of parasitologists for years to come, we encourage parasitologists to be more responsive to new approaches that provide the tools to address broader questions.


Subject(s)
Genetic Techniques/instrumentation , Molecular Biology/methods , Parasitology/methods , Molecular Biology/instrumentation , Parasitology/instrumentation
7.
Mol Vis ; 24: 690-699, 2018.
Article in English | MEDLINE | ID: mdl-30405307

ABSTRACT

Purpose: To compare methods for homogenizing the mouse whole eye or retina for RNA extraction. Methods: We tested five homogenization techniques for the whole eye and the retina. Two established shearing techniques were a version of the Potter-Elvehjem homogenizer, which uses a plastic pellet pestle in a microfuge tube, and a Dounce homogenizer. Two modern bead-beating methods used commercially manufactured devices, the Next Advance Bullet Blender and the Qiagen TissueLyser LT. The last method involved vortex mixing multiple samples simultaneously in a buffer containing a stainless-steel set screw, a novel approach. RNA was extracted from the tissue after each technique was used. Degradation of RNA was measured with the RNA integrity number (RIN score) after electrophoresis on an Agilent BioAnalyzer RNA LabChip. Nucleic acid yields were measured with ultraviolet (UV) spectroscopy in a BioTek Synergy H1 Hybrid plate reader. The purity of the nucleic acids was assessed with the mean absorbance ratio (A260/A280). The preparation time per sample was measured with a digital stopwatch. Costs of necessary consumables were calculated per ten samples. Results: The RIN scores for all homogenization methods and both tissue types ranged from 7.75±0.64 to 8.78±0.18; none were statistically significantly different. The total RNA yield per whole eye from the bead-based methods ranged from 7,700 to 9,800 ng and from 3,000 to 4,600 ng for the pellet pestle and Dounce shearing methods, respectively. The total RNA yield per retina from the bead-based methods ranged from 4,600 to 8,400 ng and from 2,200 to 7,400 ng for the pellet pestle and Dounce shearing methods, respectively. Homogenization was faster using the bead-based methods (about 15 min for ten samples) because multiple samples could be run simultaneously compared to the shearing methods that require samples be homogenized individually (about 45-60 min per ten samples). The costs in consumables for the methods tested ranged from $2.60 to $14.70 per ten samples. The major differences in overall costs come in the form of one-time equipment purchases, which can range from one hundred to thousands of dollars. The bead-based methods required less technician involvement and had less potential for sample contamination than the shearing methods. Conclusions: The purity and quality of RNA were similar across all methods for both tissue types. The novel set screw method and the two bead-based methods (bullet blender and TissueLyser) outperformed the two shearing methods (the pellet pestle and Dounce techniques) in total RNA yields for the whole eye. Although the bullet blender, TissueLyser, and set screw methods produced comparable levels of RNA yield, purity, and quality, the set screw method was less expensive. Researchers seeking the efficiency of sophisticated bead homogenization equipment without the high equipment costs might consider this novel method.


Subject(s)
Eye/chemistry , Genetic Techniques/instrumentation , RNA/isolation & purification , Retina/chemistry , Specimen Handling/methods , Animals , Mice , Mice, Inbred BALB C
8.
Lett Appl Microbiol ; 66(1): 32-37, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29117447

ABSTRACT

The aim of this work was to evaluate a fungal DNA extraction procedure with the lowest inputs in terms of time as well as of expensive and toxic chemicals, but able to consistently produce genomic DNA of good quality for PCR purposes. Two types of fungal biological material were tested - mycelium and conidia - combined with two protocols for DNA extraction using Sodium Dodecyl Sulphate (SDS) and Cetyl Trimethyl Ammonium Bromide as extraction buffers and glass beads for mechanical disruption of cell walls. Our results showed that conidia and SDS buffer was the combination that lead to the best DNA quality and yield, with the lowest variation between samples. This study clearly demonstrates that it is possible to obtain high yield and pure DNA from pigmented conidia without the use of strong cell disrupting procedures and of toxic reagents. SIGNIFICANCE AND IMPACT OF THE STUDY: There are numerous methods for DNA extraction from fungi. Some rely on expensive commercial kits and/or equipments, unavailable for many laboratories, or make use of toxic chemicals such as chloroform, phenol and mercaptoethanol. This study clearly demonstrates that it is possible to obtain high yields of pure DNA from pigmented conidia without the use of strong and expensive cell disrupting procedures and of toxic reagents. The method herein described is simultaneously inexpensive and adequate to DNA extraction from several different types of fungi.


Subject(s)
DNA, Fungal/genetics , Equipment and Supplies/economics , Fungi/genetics , Genetic Techniques/instrumentation , Cell Wall/chemistry , DNA, Fungal/isolation & purification , Fungi/isolation & purification , Genetic Techniques/economics , Indicators and Reagents/toxicity , Laboratories/economics , Polymerase Chain Reaction , Spores, Fungal/chemistry
9.
J Exp Bot ; 68(15): 4045-4056, 2017 07 10.
Article in English | MEDLINE | ID: mdl-28472492

ABSTRACT

Transport proteins are crucial for cellular function at all levels. Numerous importers and exporters facilitate transport of a diverse array of metabolites and ions intra- and intercellularly. Identification of transporter function is essential for understanding biological processes at both the cellular and organismal level. Assignment of a functional role to individual transporter proteins or to identify a transporter with a given substrate specificity has notoriously been challenging. Recently, major advances have been achieved in function-driven screens, phenotype-driven screens, and in silico-based approaches. In this review, we highlight examples that illustrate how new technology and tools have advanced identification and characterization of plant transporter functions.


Subject(s)
Botany/methods , Carrier Proteins/genetics , Genetic Techniques , Plant Proteins/genetics , Plants/metabolism , Biological Transport , Botany/instrumentation , Carrier Proteins/metabolism , Genetic Techniques/instrumentation , Plant Proteins/metabolism , Plants/genetics
10.
Anal Chem ; 87(15): 7872-9, 2015 Aug 04.
Article in English | MEDLINE | ID: mdl-26125635

ABSTRACT

The 2009 Influenza A (H1N1) pandemic disproportionately affected the developing world and highlighted the key inadequacies of traditional diagnostic methods that make them unsuitable for use in resource-limited settings, from expensive equipment and infrastructure requirements to unacceptably long turnaround times. While rapid immunoassay diagnostic tests were much less costly and more context-appropriate, they suffered from drastically low sensitivities and high false negative rates. An accurate, sensitive, and specific molecular diagnostic that is also rapid, low-cost, and independent of laboratory infrastructure is needed for effective point-of-care detection and epidemiological control in these developing regions. We developed a paper-based assay that allows for the extraction and purification of RNA directly from human clinical nasopharyngeal specimens through a poly(ether sulfone) paper matrix, H1N1-specific in situ isothermal amplification directly within the same paper matrix, and immediate visual detection on lateral flow strips. The complete sample-to-answer assay can be performed at the point-of-care in just 45 min, without the need for expensive equipment or laboratory infrastructure, and it has a clinically relevant viral load detection limit of 10(6) copies/mL, offering a 10-fold improvement over current rapid immunoassays.


Subject(s)
Genetic Techniques , Influenza A Virus, H1N1 Subtype/genetics , Influenza, Human/diagnosis , RNA/genetics , Genetic Techniques/economics , Genetic Techniques/instrumentation , Genetic Techniques/standards , Humans , Influenza A Virus, H1N1 Subtype/chemistry , Influenza A Virus, H1N1 Subtype/isolation & purification , Limit of Detection , Paper , Point-of-Care Systems , RNA/chemistry
11.
Proc Biol Sci ; 282(1810)2015 Jul 07.
Article in English | MEDLINE | ID: mdl-26108630

ABSTRACT

Genetic technologies based on transposon-mediated transgenesis along with several recently developed genome-editing technologies have become the preferred methods of choice for genetically manipulating many organisms. The silkworm, Bombyx mori, is a Lepidopteran insect of great economic importance because of its use in silk production and because it is a valuable model insect that has greatly enhanced our understanding of the biology of insects, including many agricultural pests. In the past 10 years, great advances have been achieved in the development of genetic technologies in B. mori, including transposon-based technologies that rely on piggyBac-mediated transgenesis and genome-editing technologies that rely on protein- or RNA-guided modification of chromosomes. The successful development and application of these technologies has not only facilitated a better understanding of B. mori and its use as a silk production system, but also provided valuable experiences that have contributed to the development of similar technologies in non-model insects. This review summarizes the technologies currently available for use in B. mori, their application to the study of gene function and their use in genetically modifying B. mori for biotechnology applications. The challenges, solutions and future prospects associated with the development and application of genetic technologies in B. mori are also discussed.


Subject(s)
Animals, Genetically Modified/genetics , Biotechnology/methods , Bombyx/genetics , Genetic Techniques/instrumentation , Animals , Animals, Genetically Modified/metabolism , Biotechnology/instrumentation , Bombyx/metabolism , Silk/metabolism
12.
Electrophoresis ; 36(16): 1920-6, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26031238

ABSTRACT

Celiac disease is an auto-immune disorder induced by ingestion of gluten in genetically predisposed individuals. Its diagnostics is more accurate using a combination of immunologic and genetic tests to detect of high levels of certain auto-antibodies and the presence human leukocyte antigen HLA-DQ2 or HLA-DQ8 genetic markers. In this work, we report the design and testing of automated microsystems combining sample treatment, storage, fluidic transport, and detection in a single platform able to carry out genetic or serologic analysis for detection of celiac disease markers. These microsystems share a common footprint and many fluidic features and are thus able to perform a complete assay. The microsystem for the genetic assay extracts and amplifies the DNA prior to detection, while the serology microsystem contains a filter and chamber for the generation and subsequent dilution of plasma. The performance of both platforms is demonstrated and compared with reference methods with an excellent correlation, which makes the developed platform amenable for clinical studies.


Subject(s)
Biomarkers/blood , Celiac Disease/blood , Electrochemical Techniques/instrumentation , Genetic Techniques/instrumentation , Immunoassay/instrumentation , Lab-On-A-Chip Devices , Autoantibodies/blood , Celiac Disease/genetics , Electrochemical Techniques/methods , Equipment Design , Humans
13.
Analyst ; 140(17): 5936-43, 2015 Sep 07.
Article in English | MEDLINE | ID: mdl-26225372

ABSTRACT

Sensitive and selective detection of point mutation is essential to molecular biology research and early clinical diagnosis. Here, we demonstrate a single quantum dot (QD)-based biosensor for DNA point mutation assay. In this assay, a mutant target (G/C) remains unchanged after the endonuclease treatment, and the polymerase chain reaction (PCR) may be initiated with the assistance of primers and polymerase, generating a large number of mutant targets. The amplified mutant targets can be captured by biotinylated probes during the process of denaturation and annealing, and Cy5-dGTP may be assembled into the biotinylated probe with the catalysis of polymerase, leading to the formation of Cy5-labeled biotinylated probes. The Cy5-labeled biotinylated probes can be further assembled onto the QD surface to obtain a Cy5-DNA-QD complex, resulting in the generation of fluorescence resonance energy transfer (FRET) between the QD donor and the Cy5 receptor. The mutant targets can be quantitatively evaluated by the measurement of Cy5 counts by total internal reflection fluorescence (TIRF) microscopy. While in the presence of wild-type targets (T/A), no Cy5-dGTP can be assembled into the biotinylated probe due to the presence of a mismatch and consequently no FRET is observed. This single QD-based biosensor exhibits high sensitivity with a detection limit of 5.3 aM (or 32 copies) and can even discriminate as low as 0.01% variant frequency from the mixture of mutant targets and wild-type ones. Importantly, this biosensor can be used for genomic analysis in human lung cancer cells, and may be further applied for an early clinical diagnosis and personalized medicine.


Subject(s)
Biosensing Techniques , DNA/analysis , Genetic Techniques/instrumentation , Quantum Dots/chemistry , Biotinylation , Carbocyanines/chemistry , Cell Line, Tumor , DNA/chemistry , DNA/genetics , DNA, Neoplasm/analysis , DNA, Neoplasm/chemistry , DNA, Neoplasm/genetics , Fluorescence Resonance Energy Transfer , Humans , Limit of Detection , Microscopy, Fluorescence , Point Mutation , Polymerase Chain Reaction
14.
Am J Hum Biol ; 27(3): 295-303, 2015.
Article in English | MEDLINE | ID: mdl-25711975

ABSTRACT

The study of epigenetics, or chemical modifications to the genome that may alter gene expression, is a growing area of interest for social scientists. Anthropologists and human biologists are interested in epigenetics specifically, as it provides a potential link between the environment and the genome, as well as a new layer of complexity for the study of human biological variation. In pace with the rapid increase in interest in epigenetic research, the range of methods has greatly expanded over the past decade. The primary objective of this article is to provide an overview of the current methods for assaying DNA methylation, the most commonly studied epigenetic modification. We will address considerations for all steps required to plan and conduct an analysis of DNA methylation, from appropriate sample collection, to the most commonly used methods for laboratory analyses of locus-specific and genome-wide approaches, and recommendations for statistical analyses. Key challenges in the study of DNA methylation are also discussed, including tissue specificity, the stability of measures, timing of sample collection, statistical considerations, batch effects, and challenges related to analysis and interpretation of data. Our hope is that this review serves as a primer for anthropologists and human biologists interested in incorporating epigenetic data into their research programs.


Subject(s)
DNA Methylation , Epigenomics/methods , Genetic Techniques/instrumentation , Epigenesis, Genetic/physiology , Gene Expression/physiology , Genetic Techniques/economics , Genome-Wide Association Study/economics , Genome-Wide Association Study/instrumentation , Humans , Specimen Handling/methods
15.
Anal Chem ; 86(20): 10208-14, 2014 Oct 21.
Article in English | MEDLINE | ID: mdl-25255368

ABSTRACT

Using photons as external triggers to realize remote-controlled release of oligonucleotide is superior to other intracellular or external stimulus. UV light is a valid photon-controlled manner due to high efficiency. However, further applications of these approaches in living cells are hampered by the large dose of UV-light irradiation. To address this issue, a simultaneous light and host/guest mediation was proposed in this paper. Gold nanoparticles (AuNPs) encoding with mercapto-ß-cyclodextrin (ßCD) served as a carried agent. Azobenzene (Azo), which was labeled on a releasing oligonucleotide, acted as a photochemically controlled switch. Ferrocene (Fc), an excellent guest for inclusion complexation by ßCD, serves as "enhancers" and shifts the equilibrium of the inclusion-exclusion process between trans-Azo and ßCD under UV-light irradiation, thus making the dose of UV-light irradiation reduced obviously. For further application, transfected green fluorescent protein (GFP)-expressing human lung cancer A549 cells were used to determine cellular uptake and gene silencing mediated by our constructed system in vivo. The results demonstrate that by employing Fc host-guest interaction, about 62.4% gene silencing was achieved within 30 min, which is significantly higher than that without Fc competition. Our strategy provides the potential for orthogonal DNA delivery and therapeutic activation that would be capable of achieving higher levels of site-specific activity and reduced amounts of side effects.


Subject(s)
DNA/chemistry , Genetic Techniques/instrumentation , Light , Cell Line, Tumor , Flow Cytometry , Gene Silencing , Gold/chemistry , Humans , Metal Nanoparticles/chemistry
16.
BMC Biotechnol ; 14: 94, 2014 Nov 14.
Article in English | MEDLINE | ID: mdl-25394494

ABSTRACT

BACKGROUND: This study compared the performance of five commercially available kits in extracting total RNA from small eukaryotic tissue samples (<15 mg). Total RNA was isolated from fathead minnow (Pimephales promelas) tissues (spleen, blood, kidney, embryo, and larvae) using the Qiagen RNeasy® Plus Mini, Qiagen RNeasy® Plus Universal, Promega Maxwell® 16 LEV simplyRNA, Ambion MagMAX™-96 and Promega SimplyRNA HT kits. Kit performance was evaluated via measures of RNA quantity (e.g., total RNA amount) and quality (e.g., ratio of absorbance at 260 and 280 nm, RNA integrity number (RIN), presence of gDNA). RESULTS: With the exception of embryos, each kit generally extracted ≥5 µg of total RNA from each sample. With regard to RNA quality, the RINs of RNA samples isolated via the Plus Mini and Maxwell® 16 kits were consistently higher than those of samples extracted via the remaining three kits and for all tissues, these kits produced intact RNA with average RIN values ≥7. The Plus Universal and SimplyRNA HT kits produced moderately degraded (RIN values <7, but ≥5), while the RNA recovered via the MagMAX™ kit tended to exhibit a high degree of degradation (RIN values <5). CONCLUSIONS: Each kit was generally capable of extracting the amount of RNA required for most downstream gene expression applications suggesting that RNA yield is unlikely to be a limiting factor for any of the kits evaluated. However, differences in the quality of RNA extracted via each of the kits indicate that these kits may differ in their ability to yield RNA acceptable for some applications. Overall, the findings of this study demonstrate that there are practical differences between commercially available RNA extraction kits that should be taken into account when selecting extraction methods to be used for isolating RNA designated for gene expression analysis.


Subject(s)
Animal Structures/chemistry , Cyprinidae/genetics , Genetic Techniques/instrumentation , RNA/isolation & purification , Animals , Automation , Cyprinidae/embryology , Male , Polymerase Chain Reaction , RNA/genetics , Reagent Kits, Diagnostic
17.
Yeast ; 31(2): 77-80, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24408512

ABSTRACT

The budding yeast Saccharomyces cerevisiae is a key model organism of functional genomics, due to its ease and speed of genetic manipulations. In fact, in this yeast, the requirement for homologous sequences for recombination purposes is so small that 40 base pairs (bp) are sufficient. Hence, an enormous variety of genetic manipulations can be performed by simply planning primers with the correct homology, using a defined set of transformation plasmids. Although designing primers for yeast transformations and for the verification of their correct insertion is a common task in all yeast laboratories, primer planning is usually done manually and a tool that would enable easy, automated primer planning for the yeast research community is still lacking. Here we introduce Primers-4-Yeast, a web tool that allows primers to be designed in batches for S. cerevisiae gene-targeting transformations, and for the validation of correct insertions. This novel tool enables fast, automated, accurate primer planning for large sets of genes, introduces consistency in primer planning and is therefore suggested to serve as a standard in yeast research. Primers-4-Yeast is available at: http://www.weizmann.ac.il/Primers-4-Yeast


Subject(s)
DNA Primers/genetics , Genetic Techniques/instrumentation , Internet/instrumentation , Saccharomyces cerevisiae/genetics , DNA Primers/metabolism , Databases, Nucleic Acid , Gene Targeting , Saccharomyces cerevisiae/metabolism , Software , Transformation, Genetic
18.
Opt Express ; 22(19): 22590-7, 2014 Sep 22.
Article in English | MEDLINE | ID: mdl-25321728

ABSTRACT

In this work, we optimize the structure of the photonic crystal fibers by using genetic algorithms to provide strong light confinement in fiber and small half diffraction angle of output beam. Furthermore, this article shows the potentials of this study, such as optimizing three purposes at the same time and the arbitrary structure design is achieved. We report two optimized results obtained by different optimization conditions. The results show that the half diffraction angle of the output beam of the photonic crystal fibers can be reduced.


Subject(s)
Algorithms , Genetic Techniques/instrumentation , Light , Equipment Design , Humans
19.
Anal Biochem ; 448: 58-64, 2014 Mar 01.
Article in English | MEDLINE | ID: mdl-24291640

ABSTRACT

This study employs a nanobioarray (NBA) chip for multiple biodetection of single base pair mutations at the Kras gene codon 12. To distinguish between the mutant and wild-type target DNAs, current bioarray methods use high-temperature hybridization of the targets to the allele-specific probes. However, these techniques need prior temperature optimization and become harder to implement in the case of the detection of multiple mutations. We aimed to detect these mutations at a single temperature (room temperature), enabled by the use of gold nanoparticles (AuNPs) on the bioarray created within nanofluidic channels. In this method, a low amount of target oligonucleotides (5fmol) and polymerase chain reaction (PCR) products (300pg) were first loaded on the AuNP surface, and then these AuNP-bound targets were introduced into the channels of a polydimethylsiloxane (PDMS) glass chip. The targets hybridized to their complementary probes at the intersection of the target channels to the pre-printed oligonucleotide probe lines on the glass surface, creating a bioarray. Using this technique, fast and high-throughput multiple discrimination of the Kras gene codon 12 were achieved at room temperature using the NBA chip, and the specificity of the method was proved to be as high as that with the temperature stringency method.


Subject(s)
DNA/analysis , Genetic Techniques/instrumentation , Gold/chemistry , Metal Nanoparticles/chemistry , Oligonucleotide Array Sequence Analysis , Proto-Oncogene Proteins/genetics , ras Proteins/genetics , Alleles , Codon , Humans , Microfluidic Analytical Techniques/instrumentation , Nucleic Acid Hybridization , Polymerase Chain Reaction , Polymorphism, Single Nucleotide , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins p21(ras) , Temperature , ras Proteins/metabolism
20.
Appl Microbiol Biotechnol ; 98(12): 5387-96, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24769904

ABSTRACT

Developing rapid and diverse microbial mutation tool is of importance to strain modification. In this review, a new mutagenesis method for microbial mutation breeding using the radio-frequency atmospheric-pressure glow discharge (RF APGD) plasma jets is summarized. Based on the experimental study, the helium RF APGD plasma jet has been found to be able to change the DNA sequences significantly, indicating that the RF APGD plasma jet would be a powerful tool for the microbial mutagenesis with its outstanding features, such as the low and controllable gas temperatures, abundant chemically reactive species, rapid mutation, high operation flexibility, etc. Then, with the RF APGD plasma generator as the core component, a mutation machine named as atmospheric and room temperature plasma (ARTP) mutation system has been developed and successfully employed for the mutation breeding of more than 40 kinds of microorganisms including bacteria, fungi, and microalgae. Finally, the prospect of the ARTP mutagenesis is discussed.


Subject(s)
Bacteria/genetics , Genetic Techniques , Mutagenesis , Bacteria/radiation effects , Genetic Techniques/instrumentation , Mutation
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