The monitoring of mosquitoes is of great importance due to their vector competence for a variety of pathogens, which have the potential to imperil human and animal health. Until now mosquito occurrence data is mainly obtained with conventional monitoring methods including active and passive approaches, which can be time- and cost-consuming. New monitoring methods based on environmental DNA (eDNA) could serve as a fast and robust complementary detection system for mosquitoes.
View Article and Find Full Text PDFMelting is a fundamental property of DNA that can be monitored by absorbance or fluorescence. PCR conveniently produces enough DNA to be directly monitored on real-time instruments with fluorescently labeled probes or dyes. Dyes monitor the entire PCR product, while probes focus on a specific locus within the amplicon.
View Article and Find Full Text PDFInvasive predatory species may alter population dynamic processes of their prey and impact biological communities and ecosystem processes. Revealing biotic interactions, however, including the relationship between predator and prey, is a difficult task, in particular for species that are hard to monitor. Here, we present a case study that documents the utility of environmental DNA analysis (eDNA) to assess predator-prey interactions between two invasive fishes (Lepomis gibbosus, Pseudorasbora parva) and two potential amphibian prey species, (Triturus cristatus, Pelobates fuscus).
View Article and Find Full Text PDFRapid cycle polymerase chain reaction (PCR) amplifies DNA in 10-30 min, while extreme PCR is complete in less than 1 min. These methods do not sacrifice quality for speed; sensitivity, specificity, and yield are equivalent or better than conventional PCR. What is required (and not widely available) is rapid, accurate control of reaction temperature during cycling.
View Article and Find Full Text PDFInositol pyrophosphates regulate diverse physiological processes; to better understand their functional roles, assessing their tissue-specific distribution is important. Here, we profiled inositol pyrophosphate levels in mammalian organs using an originally designed liquid chromatography-mass spectrometry (LC-MS) protocol and discovered that the gastrointestinal tract (GIT) contained the highest levels of diphosphoinositol pentakisphosphate (IP) and its precursor inositol hexakisphosphate (IP). Although their absolute levels in the GIT are diet dependent, elevated IP metabolism still exists under dietary regimens devoid of exogenous IP.
View Article and Find Full Text PDFWe used stopped-flow to monitor hypochromicity for 43 oligonucleotide duplexes to study nucleic acid kinetics and extract transition-state parameters for association and dissociation. Reactions were performed in 1.0 M NaCl (for literature comparisons) and 2.
View Article and Find Full Text PDFThe analysis of myo-inositol phosphates (InsPs) and myo-inositol pyrophosphates (PP-InsPs) is a daunting challenge due to the large number of possible isomers, the absence of a chromophore, the high charge density, the low abundance, and the instability of the esters and anhydrides. Given their importance in biology, an analytical approach to follow and understand this complex signaling hub is desirable. Here, capillary electrophoresis (CE) coupled to electrospray ionization mass spectrometry (ESI-MS) is implemented to analyze complex mixtures of InsPs and PP-InsPs with high sensitivity.
View Article and Find Full Text PDFSodium/potassium-transporting adenosine triphosphatase (Na/K-ATPase) is one of the most abundant cell membrane proteins and is essential for eukaryotes. Endogenous negative regulators have long been postulated to play an important role in regulating the activity and stability of Na/K-ATPase, but characterization of these regulators has been elusive. Mechanisms of regulating Na/K-ATPase homeostatic turnover are unknown.
View Article and Find Full Text PDFReverse transcription (RT)-PCR, the principal diagnostic method applied in the world-wide struggle against COVID-19, is capable of detecting a single molecule of a viral genome. Correctly designed and practiced RT-PCR assays for SARS-CoV-2 should not cross react with similar but distinct viral pathogens, such as the coronaviruses associated with the common cold, and should perform with very high analytical sensitivity. This analytical performance is predicated on the ability of the method to detect the presence of the selected nucleic acid target, without detection of a false positive signal.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
August 2020
Regulation of enzymatic 5' decapping of messenger RNA (mRNA), which normally commits transcripts to their destruction, has the capacity to dynamically reshape the transcriptome. For example, protection from 5' decapping promotes accumulation of mRNAs into processing (P) bodies-membraneless, biomolecular condensates. Such compartmentalization of mRNAs temporarily removes them from the translatable pool; these repressed transcripts are stabilized and stored until P-body dissolution permits transcript reentry into the cytosol.
View Article and Find Full Text PDFModeling of genomic profiles from the Cancer Genome Atlas (TCGA) by using recently developed mathematical frameworks has associated a genome-wide pattern of DNA copy-number alterations with a shorter, roughly one-year, median survival time in glioblastoma (GBM) patients. Here, to experimentally test this relationship, we whole-genome sequenced DNA from tumor samples of patients. We show that the patients represent the U.
View Article and Find Full Text PDFUnderstanding reverse transcriptase (RT) activity is critical for designing fast one-step RT-PCRs. We report a stopped-flow assay that monitors SYBR Green I fluorescence to investigate RT activity in PCR conditions. We studied the influence of PCR conditions on RT activity and assessed the accuracy of cDNA synthesis predictions for one-step RT-PCR.
View Article and Find Full Text PDFHomeostasis of cellular fluxes of inorganic phosphate (Pi) supervises its structural roles in bones and teeth, its pervasive regulation of cellular metabolism, and its functionalization of numerous organic compounds. Cellular Pi efflux is heavily reliant on Xenotropic and Polytropic Retrovirus Receptor 1 (XPR1), regulation of which is largely unknown. We demonstrate specificity of XPR1 regulation by a comparatively uncharacterized member of the inositol pyrophosphate (PP-InsP) signaling family: 1,5-bis-diphosphoinositol 2,3,4,6-tetrakisphosphate (InsP).
View Article and Find Full Text PDFQuantitative PCR (qPCR) allows the precise measurement of DNA concentrations and is generally considered to be straightforward and trouble free. However, analyses using validated Sybr Green I-based assays regularly amplify both the correct product and an artifact. Amplification of more than 1 product can be recognized when melting curve analysis is performed after the qPCR.
View Article and Find Full Text PDFActive species reintroduction is an important conservation tool when aiming for the restoration of biological communities and ecosystems. The effective monitoring of reintroduction success is a crucial factor in this process. Here, we used a combination of environmental DNA (eDNA) techniques and species distribution models (SDMs) to evaluate the success of recent reintroductions of the freshwater fish Alburnoides bipunctatus in central Germany.
View Article and Find Full Text PDFThe maintenance of cellular phosphate (Pi) homeostasis is of great importance in living organisms. The SPX domain-containing protein 1 (SPX1) proteins from both Arabidopsis and rice have been proposed to act as sensors of Pi status. The molecular signal indicating the cellular Pi status and regulating Pi homeostasis in plants, however, remains to be identified, as Pi itself does not bind to the SPX domain.
View Article and Find Full Text PDFThe kinetic requirements of quantitative PCR were experimentally dissected into the stages of DNA denaturation, primer annealing, and polymerase extension. The temperature/time conditions for 2 stages were kept optimal, while the other was limited until the amplification efficiency decreased as measured by an increase in quantification cycle (Cq). Extension was studied in a commercial capillary LightCycler®.
View Article and Find Full Text PDFBackground: Mass cytometry can differentiate more channels than conventional flow cytometry. However, for clinical use, standardization and agreement with well-established methods is paramount. We compared mass cytometry to standard clinical flow cytometry.
View Article and Find Full Text PDFAmong many cellular functions, inositol pyrophosphates (PP-InsPs) are metabolic messengers involved in the regulation of glucose uptake, insulin sensitivity, and weight gain. However, their mechanisms of action are still poorly understood. So far, the influence of PP-InsPs on cellular metabolism has been studied by overexpression or knockout/inhibition of relevant metabolizing kinases (IP6Ks, PPIP5Ks).
View Article and Find Full Text PDFBackground: Extreme PCR in <30 s and high-speed melting of PCR products in <5 s are recent advances in the turnaround time of DNA analysis. Previously, these steps had been performed on different specialized instruments. Integration of both extreme PCR and high-speed melting with real-time fluorescence monitoring for detection and genotyping is presented here.
View Article and Find Full Text PDFAcidocalcisomes of and the acidocalcisome-like vacuoles of are acidic calcium compartments that store polyphosphate (polyP). Both organelles possess a phosphate-sodium symporter (TbPho91 and Pho91p in and yeast, respectively), but the roles of these transporters in growth and orthophosphate (P) transport are unclear. We found here that trypanosomes have a lower growth rate under phosphate starvation and contain larger acidocalcisomes that have increased P content.
View Article and Find Full Text PDFAlthough myo-inositol pyrophosphates such as diphosphoinositol pentakisphosphate (InsP) are important in biology, little quantitative information is available regarding their presence in mammalian organisms owing to the technical difficulties associated with accurately detecting these materials in biological samples. We have developed an analytical method whereby InsP and its precursor inositol hexakisphosphate (InsP) are determined directly and sensitively using tandem mass spectrometry coupled with hydrophilic interaction liquid chromatography (HILIC). InsP and InsP peak symmetry is influenced greatly by the buffer salt composition and pH of the mobile phase used in HILIC analysis.
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