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1.
J Nematol ; 56(1): 20240023, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38975564

ABSTRACT

Recombinase polymerase amplification (RPA) is an isothermal in vitro nucleic acid amplification technique that has been adopted for simple, robust, rapid, reliable diagnostics of nematodes. In this study, the real-time RPA assay and RPA assay combined with lateral flow dipsticks (LF-RPA) have been developed targeting the ITS rRNA gene of the British root-knot nematode, Meloidogyne artiellia. The assay provided specific and rapid detection of this root-knot nematode species from crude nematode extracts without a DNA extraction step with a sensitivity of 0.125 second-stage juvenile (J2) specimen per a reaction tube for real-time RPA during 11 min and a sensitivity of 0.5 J2 specimens per a reaction tube for LF-RPA during 25 min. The RPA assays were validated with a wide range of non-target root-knot nematodes. The LF-RPA assay has great potential for nematode diagnostics in the laboratory having minimal available equipment.

2.
Mycobiology ; 52(3): 172-182, 2024.
Article in English | MEDLINE | ID: mdl-38948453

ABSTRACT

Truffles, belonging to the genus Tuber, are ectomycorrhizal (ECM) fungi that form underground ascocarps and primarily establish symbiosis with oaks and hazels. The cultivation of Tuber spp. involves transplanting inoculated seedlings that have formed ectomycorrhiza with Tuber species, with mulching being effective for truffle cultivation. In this study, we investigated the effects of mulching on the mycelial growth of four Tuber species (T. himalayense, T. koreanum, T. melanosporum, and T. borchii) in the Korean natural environment, highlighting the potential for Korea as a truffle cultivation site. We developed and tested species-specific primers for quantifying the soil mycelial biomass of Tuber spp. by qRT-PCR, determined the superior mulch color for mycelial growth, and identified the Tuber species exhibiting the highest growth rate in the Korean field environment. Our results demonstrated that white mulch significantly enhanced mycelial growth in Tuber species than black mulch, likely owing to its ability to maintain low soil temperatures, control weeds, and improve host plant growth. Among the Tuber species, T. himalayense showed the greatest growth potential in the Korean natural environment. Additionally, a significant and positive correlation was observed between the mycelial biomass of Tuber species and the growth of inoculated seedlings, as measured by the total stem length and the number of leaves, thereby indicating the importance of symbiosis between ECM fungi and host plants. This study provides valuable insights into truffle cultivation in Korea and highlights the potential of using white mulch to promote mycelial growth, thereby contributing essential data for understanding the appropriate environmental conditions for Tuber spp. cultivation in Korea. Further study is needed to assess the long-term impact of mulching and to explore the effectiveness of other mulching materials.

3.
Braz J Microbiol ; 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38987524

ABSTRACT

The significance of the Southern Ocean (SO) as a sink of atmospheric CO2 and other greenhouse gases is well established. Earlier studies have highlighted the role of microbes in various SO ecosystem processes. However, the diversity and role of actinobacteria in the Indian sector of SO (ISO) water and sediments are unknown. This study aimed to analyze the diversity of actinobacteria in water and sediment samples of SO based on amplicon microbiome analyses. The taxonomic analysis identified a total number of 27 phyla of which Proteobacteria (40.2%), Actinobacteria (13.6%), and Firmicutes (8.7%) were found to be dominant. The comparative study of water and sediment samples revealed the dominance of different actinobacteria in water and sediments. While the order Streptomycetales was dominant in the water samples, Micrococcales was found to be dominant in the sediment samples. The genus level analysis found the presence of eight and seventeen genera in the sediment and water samples, respectively. The genus Streptomyces, Saccharopolyspora, Nocardioides, Sva0996 marine group, and Mycobacterium were seen both in sediment and water samples. Marmoricola, Ilumatobacter, and Glaciihabitans were observed only in sediment samples whereas Rhodococcus, Corynebacterium, Micrococcus, Turicella, Pseudonocardia, Bifidobacterium, Nesterenkonia, Collinsella, Knoellia, Cadidatus, Actinomarina, Libanicoccus and Cutibacterium were noticed exclusively in water samples. Our study also emphasizes the need for further detailed study to understand the links between actinobacterial diversity and their ecological functions in the ISO. The available metabarcoding data paves the way for future research in cultivable forms of novel and rare Actinobacteria for their bioprospecting applications.

4.
Mol Med Rep ; 30(3)2024 09.
Article in English | MEDLINE | ID: mdl-38963022

ABSTRACT

As sequencing technology transitions from research to clinical settings, due to technological maturity and cost reductions, metagenomic next­generation sequencing (mNGS) is increasingly used. This shift underscores the growing need for more cost­effective and universally accessible sequencing assays to improve patient care and public health. Therefore, targeted NGS (tNGS) is gaining prominence. tNGS involves enrichment of target pathogens in patient samples based on multiplex PCR amplification or probe capture with excellent sensitivity. It is increasingly used in clinical diagnostics due to its practicality and efficiency. The present review compares the principles of different enrichment methods. The high positivity rate of tNGS in the detection of pathogens was found in respiratory samples with specific instances. tNGS maintains high sensitivity (70.8­95.0%) in samples with low pathogen loads, including blood and cerebrospinal fluid. Furthermore, tNGS is effective in detecting drug­resistant strains of Mycobacterium tuberculosis, allowing identification of resistance genes and guiding clinical treatment decisions, which is difficult to achieve with mNGS. In the present review, the application of tNGS in clinical settings and its current limitations are assessed. The continued development of tNGS has the potential to refine diagnostic accuracy and treatment efficacy and improving infectious disease management. However, further research to overcome technical challenges such as workflow time and cost is required.


Subject(s)
Communicable Diseases , High-Throughput Nucleotide Sequencing , Humans , High-Throughput Nucleotide Sequencing/methods , Communicable Diseases/diagnosis , Communicable Diseases/microbiology , Communicable Diseases/genetics , Metagenomics/methods , Molecular Diagnostic Techniques/methods
5.
Biosens Bioelectron ; 261: 116473, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-38878701

ABSTRACT

Sensitive monitoring of luteinizing hormone (LH), a glycoprotein that regulates the synthesis of regulatory steroid hormones, can facilitate the diagnosis of various reproductive diseases. In this work, a new and highly catalytic Sulfur-doped and bimetal-coordinated CoFe(CN)5NO (denoted as S-CoFe(CN)5NO) nanoparticles are synthesized. Such material is further used to construct high performance sensing interface and coupled with primer exchange reaction (PER) and hybridization chain reaction (HCR) amplification cascades for sensitive electrochemical aptamer-based LH assay. Target LH molecules bind aptamer sequences in DNA duplex probes to liberate ssDNA strands, which initiate subsequent PER/HCR amplification cascades for the capture of many ferrocene (Fc)-tagged DNAs on sensing interface. S-CoFe(CN)5NO subsequently leads to catalytic oxidation of these Fc tags for yielding substantially magnified currents for realizing ultrasensitive assay of LH with the detection limit of 0.69 pM in range from 5 pM to 10 nM. Owing to the high specificity of aptamer, such sensor has high selectivity and can achieve low levels of LH assay in diluted serum samples. With the successful demonstration for detecting trace LH, such sensor can be easily extended as a universal aptamer-based electrochemical sensing method for monitoring various target analytes in the biomedical and biological fields.


Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , Electrochemical Techniques , Limit of Detection , Luteinizing Hormone , Aptamers, Nucleotide/chemistry , Biosensing Techniques/methods , Humans , Electrochemical Techniques/methods , Luteinizing Hormone/blood , Luteinizing Hormone/chemistry , Catalysis , Sulfur/chemistry , Metal Nanoparticles/chemistry , Cobalt/chemistry , Nucleic Acid Hybridization , Nanoparticles/chemistry , Ferrous Compounds/chemistry
6.
Microbiol Spectr ; : e0429223, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38916349

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an RNA virus that undergoes rapid mutation. Based on viral whole genome sequencing analysis in Hebei Province, China, we identified several essential single nucleotide variants (SNVs) on primer-probe regions accumulating within some Omicron variants' genomes. In this study, we focused on three SNVs, C28290T, T28297C, and C28311T emerging on 2019-nCoV-N1 (CDC-N1) primer-probe regions, recommended by CDC in 2020, and two SNVs, C26270T, A26275G emerging on E (Charité-E) primer-probe regions recommended by Charité, Germany. Our findings revealed that the presence of one or two SNVs in the primer or probe region affected the sensitivity of reverse transcription-quantitative polymerase chain reaction and droplet digital PCR to varying extents. This discovery underscores the importance of continuously monitoring the whole genome sequences of SARS-CoV-2 variants, especially the primer-probe targeting regions, and correspondingly updating commercial test kits or recommended primer-probe sequence sets. IMPORTANCE: The emergence of new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants has resulted in a growing number of mutations in its genome, presenting new challenges for the diagnosis of SARS-CoV-2 using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and droplet digital PCR (RT-ddPCR) methods. There is an urgent need to develop refined methods for modifying primers and probes to improve the detection of these emerging variants. In this study, our focus was on the SNVs that have emerged in the CDC-N1 and Charité-E primer-probe regions. Our research has confirmed that the presence of these SNVs in the primer or probe region can significantly affect the results of coronavirus disease 2019 tests. we have developed and validated a modified detection method that can provide higher sensitivity and specificity. This study emphasizes the importance of refining the primer-probe sets to ensure the diagnostic accuracy of RT-qPCR and RT-ddPCR detection.

7.
Mitochondrial DNA B Resour ; 9(6): 771-776, 2024.
Article in English | MEDLINE | ID: mdl-38919811

ABSTRACT

Here, we present the mitochondrial sequences of two sea slugs (Heterobranchia): Runcina aurata and Facelina auriculata, the latter being the type species of the family. The mitochondrial genomes are 14,282 and 14,171bp in length, respectively, with a complete set of 13 PCGs, 2 rRNAs, and 22 tRNAs. None of the mitogenomes show gene reorganization, keeping the standard mitogenomic structure of Heterobranchia. Nucleotide composition differs significantly between them, with R. aurata showing the most AT-rich mitogenome (25.7% GC content) reported to date in Heterobranchia, and F. auriculata showing a rich GC content (35%) compared with other heterobranch mitochondrial genomes.

8.
Dent J (Basel) ; 12(6)2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38920889

ABSTRACT

This in vitro study assessed the effect of different primers on the shear bond strength (SBS) and adhesive remnant index (ARI) of orthodontic brackets bonded to reinforced polyetheretherketone (PEEK) substrate. A total of 40 specimens were randomly distributed to two groups based on the primer used for orthodontic bonding: group 1 (control)-Transbond XT adhesive with Visio.link primer and group 2 (test)-orthodontic adhesive (Transbond XT) with traditional orthodontic primer. After bonding, specimens were thermocycled followed by SBS testing and ARI scoring of debonded specimens. Data were analyzed using the unpaired independent t-test and the Chi-square test. Group 1 specimens showed significantly higher SBS values (21.38 ± 1.48 MPa) compared to group 2 specimens (18.63 ± 1.29 MPa) (p < 0.0001). Adhesive remnant index scores showed no significant variations in bond failure modes and distributions between groups. The SBS obtained by the tested primers exceeded the clinically recommended value. Consequently, there is a comparable clinical application for both tested primers in orthodontic bonding, especially the traditional orthodontic primer, where the availability of Visio.link in clinical practice is not ensured.

9.
Methods Mol Biol ; 2809: 145-156, 2024.
Article in English | MEDLINE | ID: mdl-38907896

ABSTRACT

The prerequisite for successful HLA genotyping is the integrity of the large allele reference database IPD-IMGT/HLA. Consequently, it is in the laboratories' best interest that the data quality of submitted novel sequences is high. However, due to its long and variable length, the gene HLA-DRB1 presents the biggest challenge and as of today only 16% of the HLA-DRB1 alleles in the database are characterized in full length. To improve this situation, we developed a protocol for long-range PCR amplification of targeted HLA-DRB1 alleles. By subsequently combining both long-read and short-read sequencing technologies, our protocol ensures phased and error-corrected sequences of reference grade quality. This dual redundant reference sequencing (DR2S) approach is of particular importance for correctly resolving the challenging repeat regions of DRB1 intron 1. Until today, we used this protocol to characterize and submit 384 full-length HLA-DRB1 sequences to IPD-IMGT/HLA.


Subject(s)
Alleles , Databases, Genetic , HLA-DRB1 Chains , HLA-DRB1 Chains/genetics , Humans , Polymerase Chain Reaction/methods , Sequence Analysis, DNA/methods , Genotype , Histocompatibility Testing/methods
10.
J Gen Virol ; 105(6)2024 Jun.
Article in English | MEDLINE | ID: mdl-38888587

ABSTRACT

Turtlegrass virus X, which infects the seagrass Thalassia testudinum, is the only potexvirus known to infect marine flowering plants. We investigated potexvirus distribution in seagrasses using a degenerate reverse transcription polymerase chain reaction (RT-PCR) assay originally designed to capture potexvirus diversity in terrestrial plants. The assay, which implements Potex-5 and Potex-2RC primers, successfully amplified a 584 nt RNA-dependent RNA polymerase (RdRp) fragment from TVX-infected seagrasses. Following validation, we screened 74 opportunistically collected, apparently healthy seagrass samples for potexviruses using this RT-PCR assay. The survey examined the host species T. testudinum, Halodule wrightii, Halophila stipulacea, Syringodium filiforme, Ruppia maritima, and Zostera marina. Potexvirus PCR products were successfully generated only from T. testudinum samples and phylogenetic analysis of sequenced PCR products revealed five distinct TVX sequence variants. Although the RT-PCR assay revealed limited potexvirus diversity in seagrasses, the expanded geographic distribution of TVX shown here emphasizes the importance of future studies to investigate T. testudinum populations across its native range and understand how the observed fine-scale genetic diversity affects host-virus interactions.


Subject(s)
Genetic Variation , Phylogeny , Potexvirus , Potexvirus/genetics , Potexvirus/isolation & purification , Potexvirus/classification , Gulf of Mexico , Plant Diseases/virology , Hydrocharitaceae/virology , RNA-Dependent RNA Polymerase/genetics , RNA, Viral/genetics , Zosteraceae/virology
11.
Plant Commun ; : 100983, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38845197

ABSTRACT

Whole-genome genotyping (WGG) stands as a pivotal element in genomic-assisted plant breeding. Nevertheless, sequencing-based approaches for WGG continue to be costly, primarily attributed to the high expenses associated with library preparation and the laborious protocol. During the prior development of Foreground and Background Integrated genotyping by sequencing (FBI-seq), we discovered that any sequence specific primer (SP) inherently possessed the capability to amplify a massive array of stable and reproducible non-specific PCR product across the genome. Here we further improved the FBI-seq by replacing the adapter ligated by Tn5 transposase with arbitrary degenerate (AD) primer. The protocol for the enhanced FBI-seq unexpectedly mirrors a simplified Thermal Asymmetric Interlaced (TAIL)-PCR, a technique widely employed for isolating flanking sequences. However, the improved TAIL-PCR maximizes the PTMA capabilities of both SP and AD primers. Additionally, leveraging next-generation sequencing enhances its ability to assay tens of thousands of genome-wide loci for any species. This cost-effective, user-friendly, and powerful WGG tool, TAIL-PCR by sequencing (TAIL-peq), holds great potential for widespread application in breeding programs, thereby facilitating genome-assisted crop improvement.

12.
Laryngoscope Investig Otolaryngol ; 9(3): e1266, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38835335

ABSTRACT

Objectives: The peer review process is critical to maintaining quality, reliability, novelty, and innovation in the scientific literature. However, the teaching of scientific peer review is rarely a component of formal scientific or clinical training, and even the most experienced peer reviewers express interest in continuing education. The objective of this review article is to summarize the collective perspectives of experienced journal editors about how to be a good reviewer in a step-by-step guide that can serve as a resource for the performance of peer review of a scientific manuscript. Methods: This is a narrative review. Results: A review of the history and an overview of the modern-day peer review process are provided with attention to the role played by the reviewer, including important reasons for involvement in scientific peer review. The general components of a scientific peer review are described, and a model for how to structure a peer review report is provided. These concepts are also summarized in a reviewer checklist that can be used in real-time to develop and double-check one's reviewer report before submitting it. Conclusions: Peer review is a critically important service for maintaining quality in the scientific literature. Peer review of a scientific manuscript and the associated reviewer's report should assess specific details related to the accuracy, validity, novelty, and interpretation of a study's results. We hope that this article will serve as a resource and guide for reviewers of all levels of experience in the performance of peer review of a scientific manuscript.

13.
J Pharm Bioallied Sci ; 16(Suppl 2): S1373-S1377, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38882726

ABSTRACT

Aim: In this, in vitro study's objective is to assess the shear bond strength (SBS) of metal and ceramic orthodontic brackets that have been adhered to enamel using a conventional acid etch/primer and self-etching primer (SEP) adhesive method. Materials and Methods: One hundred excised human premolars were bonded on brackets and were divided into group 1 -Metal brackets were bonded on teeth and group 2 -Ceramic brackets were bonded on teeth. These two groups were further subdivided: subgroup 1a - 25 metal brackets bonded using conventional acid etch/primer adhesive system, subgroup 1b - 25 metal brackets bonded using SEP, subgroup 2a - 25 ceramic brackets bonded using conventional acid etch/primer adhesive system, and subgroup 2b - 25 ceramic brackets bonded using SEP; brackets were debonded using a computerized Instron universal testing machine. Results: The mean value of SBS of metal and ceramic brackets bonded using conventional acid etch/primer adhesive systems had higher SBS than those bonded using SEP. SBS ranged from 7.95 to 12.24 MPa which was in the acceptable clinical range. Conclusion: SBS values of all four subgroups exceeded the range of 6-8 MPa observed to be acceptable for routine clinical use.

14.
J Pharm Bioallied Sci ; 16(Suppl 2): S1287-S1290, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38882782

ABSTRACT

Aeromonas hydrophila is a Gram-negative bacterium that has been linked to serious illnesses in both humans and animals. The presence of hemolysin, a virulence factor, is critical in the development of A. hydrophila-related illnesses. As a result, precise and timely detection of the hemolysin gene is critical for efficient diagnosis and prevention of many illnesses. The PCR is used in this study to detect the hemolysin gene of A. hydrophila in a novel, fast, and highly sensitive one-step technique. Specific primers were constructed to amplify a conserved area within the hemolysin gene to achieve both specificity as well as sensitivity. The PCR assay was rigorously optimized, taking temperature, primer concentration, and reaction time into account, in order to maximize the efficiency and reliability of this method. In conclusion, this method's simplicity, sensitivity, and specificity make it highly promising for regular diagnostic applications. Its application would allow for the early detection of A. hydrophila infections, allowing for more effective treatment and control methods.

15.
J Int Soc Prev Community Dent ; 14(2): 105-111, 2024.
Article in English | MEDLINE | ID: mdl-38827357

ABSTRACT

Background: Single-component adhesives do not require the application of a primer on the enamel surface that has been etched and has been reported to have acceptable shear bond strengths on in vitro evaluation. Aim: This split-mouth study aimed to examine and assess the rates of bracket bond failure of hydroxyethyl methacrylate (HEMA)-based (Aqualine LC) and bisphenol A-glycidyl methacrylate (BisGMA)-based (Orthofix SPA) single-component adhesives used to bond orthodontic brackets over 6 months. Materials and Methods: This in vivo study involved the participation of 50 adult subjects, with 1080 metallic brackets directly bonded to the labial/facial surface in a split-mouth design. After 6 months of treatment, 49 patients with 490 brackets bonded using a HEMA-based adhesive and 490 brackets bonded using a BisGMA-based adhesive were evaluated for bracket bond failures. Descriptive statistics and chi-square tests were done to compare the results. Results: The overall bracket bond failure rate (BFR) with single-component adhesives was 6.02%. Bracket BFRs of HEMA-based and BisGMA-based adhesives were 4.16% and 7.8%, respectively, and the difference was statistically significant (P < 0.05). Significant differences in BFRs between maxillary teeth (4.28%) and mandibular teeth (7.75%) were noted (P < 0.05). No significant differences in bond failures between either side or region were noted. Conclusion: Bond failures were more in brackets bonded with BisGMA-based adhesive (Orthofix SPA) compared with HEMA-based adhesive (Aqualine LC). Bond failures were less in the maxillary arch.

16.
BMC Plant Biol ; 24(1): 509, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38844865

ABSTRACT

BACKGROUND: Among the Citrus species, lemon (Citrus limon Burm f.) is one of the most affected by the two-spotted spider mite (Tetranychus urticae Koch). Moreover, chemical control is hampered by the mite's ability to develop genetic resistance against acaricides. In this context, the identification of the genetic basis of the host resistance could represent a sustainable strategy for spider mite control. In the present study, a marker-trait association analysis was performed on a lemon population employing an association mapping approach. An inter-specific full-sib population composed of 109 accessions was phenotyped through a detached-leaf assays performed in modified Huffaker cells. Those individuals, complemented with two inter-specific segregating populations, were genotyped using a target-sequencing approach called SPET (Single Primer Enrichment Technology), the resulting SNPs were employed for the generation of an integrated genetic map. RESULTS: The percentage of damaged area in the full-sib population showed a quantitative distribution with values ranging from 0.36 to 9.67%. A total of 47,298 SNPs were selected for an association mapping study and a significant marker linked with resistance to spider mite was detected on linkage group 5. In silico gene annotation of the QTL interval enabled the detection of 13 genes involved in immune response to biotic and abiotic stress. Gene expression analysis showed an over expression of the gene encoding for the ethylene-responsive transcription factor ERF098-like, already characterized in Arabidopsis and in rice for its involvement in defense response. CONCLUSION: The identification of a molecular marker linked to the resistance to spider mite attack can pave the way for the development of marker-assisted breeding plan for the development of novel selection coupling favorable agronomical traits (e.g. fruit quality, yield) with a higher resistance toward the mite.


Subject(s)
Citrus , Polymorphism, Single Nucleotide , Quantitative Trait Loci , Tetranychidae , Animals , Tetranychidae/genetics , Tetranychidae/physiology , Citrus/genetics , Citrus/parasitology , Plant Diseases/parasitology , Plant Diseases/genetics , Plant Diseases/immunology , Chromosome Mapping , Disease Resistance/genetics
17.
BMC Genomics ; 25(1): 594, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38867172

ABSTRACT

BACKGROUND: Reverse transcription quantitative PCR (RT-qPCR) with intercalating dyes is one of the main techniques to assess gene expression levels used in basic and applied research as well as in diagnostics. However, primer design for RT-qPCR can be complex due to the high demands on primer quality. Primers are best placed on exon junctions, should avoid polymorphic regions, be specific to the target transcripts and also prevent genomic amplification accurately, among others. Current software tools manage to meet all the necessary criteria only insufficiently. Here, we present ExonSurfer, a novel, user-friendly web-tool for qPCR primer design. RESULTS: ExonSurfer combines the different steps of the primer design process, encompassing target selection, specificity and self-complementarity assessment, and the avoidance of issues arising from polymorphisms. Amplification of potentially contaminating genomic DNA is avoided by designing primers on exon-exon junctions, moreover, a genomic alignment is performed to filter the primers accordingly and inform the user of any predicted interaction. In order to test the whole performance of the application, we designed primer pairs for 26 targets and checked both primer efficiency, amplicon melting temperature and length and confirmed the targeted amplicon by Sanger sequencing. Most of the tested primers accurately and selectively amplified the corresponding targets. CONCLUSION: ExonSurfer offers a comprehensive end-to-end primer design, guaranteeing transcript-specific amplification. The user interface is intuitive, providing essential specificity and amplicon details. The tool can also be used by command line and the source code is available. Overall, we expect ExonSurfer to facilitate RT-qPCR set-up for researchers in many fields.


Subject(s)
DNA Primers , Exons , Internet , Software , DNA Primers/genetics , Humans , Reverse Transcriptase Polymerase Chain Reaction/methods
18.
Methods Mol Biol ; 2808: 19-33, 2024.
Article in English | MEDLINE | ID: mdl-38743360

ABSTRACT

Morbilliviruses such as measles virus (MeV) are responsible for major morbidity and mortality worldwide, despite the availability of an effective vaccine and global vaccination campaigns. MeV belongs to the mononegavirus order of viral pathogens that store their genetic information in non-segmented negative polarity RNA genomes. Genome replication and viral gene expression are carried out by a virus-encoded RNA-dependent RNA polymerase (RdRP) complex that has no immediate host cell analog. To better understand the organization and regulation of the viral RdRP and mechanistically characterize antiviral candidates, biochemical RdRP assays have been developed that employ purified recombinant polymerase complexes and synthetic RNA templates to monitor the initiation of RNA synthesis and RNA elongation in vitro. In this article, we will discuss strategies for the efficient expression and preparation of mononegavirus polymerase complexes, provide detailed protocols for the execution and optimization of RdRP assays, evaluate alternative options for the choice of template and detection system, and describe the application of the assay for the characterization of inhibitor candidates. Although MeV RdRP assays are the focus of this article, the general strategies and experimental approaches are readily transferable to related viruses in the mononegavirus order.


Subject(s)
Measles virus , RNA-Dependent RNA Polymerase , Virus Replication , Measles virus/genetics , RNA-Dependent RNA Polymerase/metabolism , RNA-Dependent RNA Polymerase/genetics , RNA, Viral/genetics , Mononegavirales/genetics , Animals , Viral Proteins/metabolism , Viral Proteins/genetics , Humans
19.
Micromachines (Basel) ; 15(5)2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38793138

ABSTRACT

The thermal stability of DNA immobilized on a solid surface is one of the factors that affects the efficiency of solid-phase amplification (SP-PCR). Although variable temperature amplification ensures high specificity of the reaction by precisely controlling temperature changes, excessively high temperatures during denaturation can negatively affect DNA stability. Formamide (FA) enables DNA denaturation at lower temperatures, showing potential for SP-PCR. Research on FA's impacts on DNA microarrays is still limited, necessitating further optimization in exploring the characteristics of FA in SP-PCR according to particular application needs. We immobilized DNA on a chip using a crosslinker and generated DNA microarrays through bridge amplification based on FA denaturation on our automated reaction device. We optimized the denaturation and hybridization parameters of FA, achieving a maximum cluster density of 2.83 × 104 colonies/mm2. Compared to high-temperature denaturation, FA denaturation required a lower template concentration and milder reaction conditions and produced higher cluster density, demonstrating that FA effectively improves hybridization rates on surfaces. Regarding the immobilized DNA stability, the FA group exhibited a 45% loss of DNA, resulting in a 15% higher DNA retention rate compared to the high-temperature group, indicating that FA can better maintain DNA stability. Our study suggests that using FA improves the immobilized DNA stability and amplification efficiency in SP-PCR.

20.
Front Genet ; 15: 1373028, 2024.
Article in English | MEDLINE | ID: mdl-38784030

ABSTRACT

Hippophae rhamnoides subsp. sinensis Rousi is a cold- and drought-tolerant pioneer species with significant economic and ecological value. Evaluating its genetic diversity and population structure is of great importance for guiding the development and utilization of resources. In this study, a total of 41,804 SSRs were generated by transcriptome sequencing of Hippophae rhamnoides subsp. sinensis Rousi. Among the different SSR motif types, mononucleotide repeats (26,972) were the most abundant, followed by trinucleotides, tetranucleotides, and pentanucleotides. 200 pairs of SSR primers were selected to detect polymorphisms, of which 15 pairs primers were selected as validated polymorphic SSRs used for genetic diversity and population structure analysis. A total of 63 alleles were identified with 15 pairs primers, with Nei's genetic diversity index ranged from 0.27 to 0.83 (average: 0.54), and the expected heterozygosity ranged from 0.16 to 0.73 (average: 0.46). The polymorphism information content ranged from 0.23 to 0.81 (average: 0.48). Genetic structure analyses showed that the 10 populations could be broadly categorized into two groups. AMOVA denoted that genetic variations primarily originated from within the populations, with minimal differences observed between the groups, accounting for only 7% of the total genetic variation. This implies that mutation in H. rhamnoides subsp. sinensis Rousi mainly occurred within the populations. The results showed that the 10 populations of H. rhamnoides subsp. sinensis Rousi are rich in genetic diversity, with low levels of population differentiation and a high degree of gene exchange, which should be taken into consideration for the future work of germplasm resource preservation and seedling breeding.

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