Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “RNA sequencing analysis”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,171 records · Page 65Linked to original sources

Characterization of Vibrio strains isolated from turbot (Scophthalmus maximus) culture by phenotypic analysis, ribotyping and 16S rRNA gene sequence comparison.

AIM: The aim of the present study was to clarify the taxonomic status of Vibrio strains isolated from an aquaculture system and to compare the results of the identifications made by phenotypic and molecular methods. METHODS AND RESULTS: Fifty-one Vibrio strains isolated from a turbot (Scophthalmus maximus) aquaculture system were characterized by ribotyping and 16S rRNA gene sequencing. The strains had been identified phenotypically in a previous numerical taxonomy analysis as Vibrio anguillarum, V. mediterranei, V. splendidus, V. aestuarianus, V. ordalii, V. fischeri and V. scophthalmi. Cluster analysis of ribotype patterns showed that the strains were separated into two main groups: V. splendidus-V. lentus and V. scophthalmi groups. The use of 16S rRNA gene sequence allowed differentiation among V. splendidus biovar I and V. lentus strains. CONCLUSIONS: The molecular methods identified strains of V. splendidus biovar I, V. lentus and V. scophthalmi, showing discrepancies with phenotypic characterization. SIGNIFICANCE AND IMPACT OF THE STUDY: The molecular methods, as 16S rRNA gene sequence analysis, are necessary for the identification of phenotypically close species to avoid mis-identifications. Interestingly, this is the first report of V. lentus strains associated to turbot culture.

Animals↗

Characterization of extracellular RNAs produced by the marine photosynthetic bacterium Rhodovulum sulfidophilum.

The marine photosynthetic bacterium Rhodovulum sulfidophilum produces extracellular nucleic acids that are involved in its flocculation. These were found to be produced concomitantly with cell growth. The RNA fraction of these extracellular nucleic acids was subjected to cDNA analysis by applying a micro RNA cloning method and found to contain mainly fully mature-sized tRNAs and fragments of 16S and 23S rRNAs. Analyses of modified bases and genes of the RNAs revealed no structural difference between the intracellular and extracellular RNAs. This is the first report of structural analyses of bacterial extracellular RNAs.

Base Sequence↗

REACTOR: REgulon Activity analysis and Comparison Tool for single-cell transcriptOmics Research.

SUMMARY: We introduce REACTOR, a computational tool designed to detect differential activity of transcriptional regulators and their target genes (regulons) in single-cell RNA-sequencing data. It expands the currently available framework for regulon analysis by introducing a robust statistical test to detect differential regulon activity between conditions, such as disease versus control, with multiple replicates. By contrasting different conditions, REACTOR enables identification of key condition- and cell type-specific regulons. To demonstrate the use of REACTOR, we illustrate its performance in a publicly available COVID-19 dataset. AVAILABILITY: REACTOR R-package together with an implementation vignette are available at https://www.github.com/elolab/REACTOR.

Regulon↗

Integrating alternative splicing detection into gene prediction.

BACKGROUND: Alternative splicing (AS) is now considered as a major actor in transcriptome/proteome diversity and it cannot be neglected in the annotation process of a new genome. Despite considerable progresses in term of accuracy in computational gene prediction, the ability to reliably predict AS variants when there is local experimental evidence of it remains an open challenge for gene finders. RESULTS: We have used a new integrative approach that allows to incorporate AS detection into ab initio gene prediction. This method relies on the analysis of genomically aligned transcript sequences (ESTs and/or cDNAs), and has been implemented in the dynamic programming algorithm of the graph-based gene finder EuGENE. Given a genomic sequence and a set of aligned transcripts, this new version identifies the set of transcripts carrying evidence of alternative splicing events, and provides, in addition to the classical optimal gene prediction, alternative optimal predictions (among those which are consistent with the AS events detected). This allows for multiple annotations of a single gene in a way such that each predicted variant is supported by a transcript evidence (but not necessarily with a full-length coverage). CONCLUSIONS: This automatic combination of experimental data analysis and ab initio gene finding offers an ideal integration of alternatively spliced gene prediction inside a single annotation pipeline.

Algorithms↗

Rational siRNA design for RNA interference.

Short-interfering RNAs suppress gene expression through a highly regulated enzyme-mediated process called RNA interference (RNAi). RNAi involves multiple RNA-protein interactions characterized by four major steps: assembly of siRNA with the RNA-induced silencing complex (RISC), activation of the RISC, target recognition and target cleavage. These interactions may bias strand selection during siRNA-RISC assembly and activation, and contribute to the overall efficiency of RNAi. To identify siRNA-specific features likely to contribute to efficient processing at each step, we performed a systematic analysis of 180 siRNAs targeting the mRNA of two genes. Eight characteristics associated with siRNA functionality were identified: low G/C content, a bias towards low internal stability at the sense strand 3'-terminus, lack of inverted repeats, and sense strand base preferences (positions 3, 10, 13 and 19). Further analyses revealed that application of an algorithm incorporating all eight criteria significantly improves potent siRNA selection. This highlights the utility of rational design for selecting potent siRNAs and facilitating functional gene knockdown studies.

Animals↗

Optimization of RNA isolation from the archaebacterium Methanosarcina barkeri and validation for oligonucleotide microarray analysis.

The recent completion of a draft genome sequence for Methanosarcina barkeri has allowed the application of various high throughput post-genomics technologies, such as nucleic acid microarrays and mass spectrometry of proteins to detect global changes in transcription and translation that occur in response to experimental treatments. However, due to the production of a thick heteropolysaccharide outer layer, M. barkeri usually grows in large aggregates of cells rather than as individual, planktonic cells. Complete disruption of these aggregates and lysis of the released cells presents technical difficulties in ensuring the isolation of intact RNA from the entire population of cells. Initial attempts at isolating RNA from M. barkeri using several standard extraction protocols gave incomplete lysis of cells and resulted in low yields of poor quality RNA. In this study, we tested several chemical and mechanical disruption modifications of standard RNA extraction methods to optimize the extraction efficiency and minimize the number of unlysed cells remaining after extraction. As a further test of the quality of the resulting RNAs, their performance in replicate microarray analyses were determined. The results showed that inclusion of a liquid nitrogen grinding step prior to Trizol extraction, combined with moderate bead beating, yielded the most complete cell lysis, the highest yield of RNA and the most reproducible microarray results for M. barkeri. From these results it is clear that the methods used to isolate RNA can have a significant impact on the variability, trend and, presumably, the accuracy of microarray data. In addition, functional analysis of the microarray results obtained with RNA from the optimized protocol showed that, as expected, the genes involved in methanogenesis were among the most highly expressed genes in M. barkeri.

Gene Expression↗

Genome-wide transcriptional analysis in S. cerevisiae by mini-array membrane hybridization.

Access to the powerful micro-array analytical methods used for genome-wide transcriptional analysis has so far been restricted by the high cost and/or lack of availability of the sophisticated instrumentation and materials needed to perform it. Mini-array membrane hybridization provides a less expensive alternative. The reliability of this technique, however, is not well documented and its reported use has, up to this point, been very limited. Our objective was to test whether or not mini-array membrane hybridization would reliably identify genes whose expression was controlled by a specific set of genetic and/or physiological signals. Our results demonstrate that mini-array hybridization can correctly identify genes whose expression is known to be controlled by the GATA-factor regulatory network in S. cerevisiae and in addition can reliably identify genes not previously reported to be associated with this nitrogen control system.

Amino Acid Sequence↗

Human saliva proteome and transcriptome.

This paper tests the hypothesis that salivary proteins and their counterpart mRNAs co-exist in human whole saliva. Global profiling of human saliva proteomes and transcriptomes by mass spectrometry (MS) and expression microarray technologies, respectively, revealed many similarities between saliva proteins and mRNAs. Of the function-known proteins identified in saliva, from 61 to 70% were also found present as mRNA transcripts. For genes not detected at both protein and mRNA levels, we made further efforts to determine if the counterpart is present. Of 19 selected genes detected only at the protein level, the mRNAs of 13 (68%) genes were found in saliva by RT-PCR. In contrast, of many mRNAs detected only by microarrays, their protein products were found in saliva, as reported previously by other investigators. The saliva transcriptome may provide preliminary insights into the boundary of the saliva proteome.

Adult↗

Decoding ALS from the tail end of RNA.

In this issue of Cell Genomics, McKeever et al.1 generate a single-nucleus transcriptomic atlas of ALS/FTLD brain and reveal widespread alternative polyadenylation changes. Their findings highlight 3' end RNA processing as a central integrator of stress responses, cell-type specificity, and disease susceptibility, offering new mechanistic insight and potential therapeutic directions.

Cell Nucleus↗

[Determination of the taxonomic position of bacteria from Lake Baikal using sequence analysis of 16S rRNA fragments].

The taxonomic position of seven strains of aquatic bacteria from Lake Baikal was determined based on the analysis of the nucleotide sequences of 16 S rRNA gene fragments. Three strains belonged to the gamma-sub-class of Proteobacteria, one strain, to the beta-subclass, and the other three stains were assigned to the genus Bacillus (gram-positive bacteria with a low G+C content).

Bacillus↗

The genetic diversity of European type PRRSV is similar to that of the North American type but is geographically skewed within Europe.

Porcine reproductive and respiratory syndrome virus (PRRSV) is a recently emerged pathogen. Two PRRSV genotypes exist, North American and European, which are only 55-70% identical at the nucleotide level. Previous studies have shown high nucleotide diversity in the North American genotype and low nucleotide diversity in the European genotype. Here, we analyzed the ORF5 and ORF7 genes for a large number of new European type PRRSV isolates in conjunction with existing database sequences. This new analysis showed that contrary to previous assumptions, genetic diversity is at least as high in the European genotype as in the North American genotype. Furthermore, we showed that genetic diversity of European type PRRSV has a marked geographical pattern, with exceptionally high genetic diversity among Italian sequences. The geographical pattern of diversity in relation to the epidemiology of PRRSV in Europe is discussed. Discrepancies between ORF5- and ORF7-based genealogies were observed, and further analysis of the data set confirmed the presence of recombination. We were therefore able to report the first observation of recombination in wild-type isolates of European genotype PRRSV.

Animals↗

RNA structure analysis assisted by capillary electrophoresis.

Although most capillary electrophoresis (CE) applications in the nucleic acid field performed so far address DNA analysis, various RNA assays by CE have also been done. Both natural and synthetic RNAs have been examined to evaluate their quantities, sizes and interactions. In this report, we show a novel application of CE in RNA research for the analysis of RNA stable conformers. First, we present a successful adaptation of two different enzymatic methods for the 3'-end labeling of RNAs with commercially available fluorescent probes. Then, we show the high performance of CE with laser-induced fluorescence detection (CE-LIF) assisting the structural studies of transcripts. Using the example of regulatory elements present in the breast cancer gene transcript BRCA1, we demonstrate-by direct comparisons-the advantages of CE-LIF over the traditional slab-gel electrophoresis. These include a better and more reproducible separation of conformers, shorter analysis time and higher detection sensitivity.

BRCA1 Protein↗

Identification of waterborne bacteria by the analysis of 16S-23S rRNA intergenic spacer region.

AIM: In this study, we evaluated, the use of universal primers, specific for the 16S-23S rRNA intergenic region, to detect and identify nine species that are of high interest for the microbiological control of water. METHODS AND RESULTS: The analysis of the fragments was carried out using a High Resolution acrylamide/bisacrylamide gels in a fluorescent automated DNA sequencer. The results showed specific profiles for each of the nine species but this technique failed to detect simultaneously micro-organisms in samples containing a mixed population. CONCLUSION: Nevertheless, the electrophoretic profiles obtained provided a very useful tool for the rapid and specific identification of water isolates. SIGNIFICANCE AND IMPACT OF THE STUDY: A possible new methodology for a rapid identification of pathogens in water.

Bacteria↗

CapSelect: a highly sensitive method for 5' CAP-dependent enrichment of full-length cDNA in PCR-mediated analysis of mRNAs.

Here we present CapSelect as a novel experimental approach for the selective enrichment of full-length cDNAs in PCR-mediated analysis of mRNA sequences. The method combines the 5'-CAP-dependent addition of specifically three to four non-templated dCMP residues to the 3'-end of full-length cDNAs by reverse transcriptases in the presence of manganese and the controlled ribonucleotide tailing of cDNA ends by terminal deoxynucleotidyl transferase using rATP. By virtue of the generated terminal sequence motif (5'-dC(3-4)rA(3-4)), full-length cDNAs are selectively anchored to a double-stranded DNA adapter (with a dT(3-4)dG(3)3'-overhang) by T4 DNA ligase. The technique described is highly efficient, discriminates premature termination products and enriches full-length cDNAs.

Cell Line↗

cDNA sequence analysis of cardiotoxin variants from Taiwan cobra.

Five cDNAs encoding cardiotoxin variants were constructed from the cellular RNA isolated from the venom glands of Naja naja atra by reverse transcription-polymerase chain reaction. A high degree of nucleotide sequence homology was observed between these variants and other determined ones. Among them, a novel cardiotoxin 6 had 61 amino acid residues rather than 60 ones that usually observed with Naja naja atra cardiotoxins. The other cardiotoxin variants were the homologues of cardiotoxins 1, V or N with one or two amino acid substitutions, respectively. These results probably reflect the involvement of RNA editing in the production of cardiotoxin variants in the venom of Taiwan cobra.

Amino Acid Sequence↗

Evidence for transfer of antibiotic-resistance genes in soil populations of streptomycetes.

Phylogenetic analysis was used to evaluate the hypothesis of gene transfer in streptomycetes, many of which are antibiotic producers. The diversity and possible origins of streptomycin-resistance genes was investigated for a population of Streptomyces strains isolated from a site in Brazil where antibiotic production had previously been implicated The analysis provides compelling evidence for the transfer of these genes. Examination of other Streptomyces-type strains also reveals a scattered distribution of streptomycin producers with respect to the overall phylogeny. These results suggest that horizontal gene transfer may be an important factor in the evolution of antibiotic genes in streptomycetes.

Anti-Bacterial Agents↗

Transcription of the trp operon in Lactococcus lactis is controlled by antitermination in the leader region.

The regulatory functions of the leader region preceding the Lactococcus lactis trp operon have been studied by mutagenesis analysis. This leader presents striking similarity to 'T-box' leaders found upstream of many Gram-positive aminoacyl-tRNA synthetase genes and some amino acid biosynthesis operons, which are controlled by antitermination through interaction of the leader transcript with cognate uncharged tRNA. A region of the L. lactis leader transcript also contains a series of (G/U) AG repeats which, in Bacillus, are involved in the binding of the trp RNA-binding protein (TRAP) which controls trp transcription. A screen was developed for the isolation of regulatory mutants affected in the leader region. All spontaneous mutants contained deletions; point mutations were only obtained after UV-induced mutagenesis. All mutations affected the putative transcription terminator upstream of the trp operon, demonstrating that trp is indeed controlled by transcription antitermination.

Base Sequence↗

16S rRNA gene sequences of 'Candidatus Campylobacter hominis', a novel uncultivated species, are found in the gastrointestinal tract of healthy humans.

Although some Campylobacter species are agents of gastroenteritis and periodontal disease in humans, little is known of the variety of campylobacters in the gastrointestinal tract of healthy individuals. This paper provides evidence for the existence of a previously undescribed, uncultivated Campylobacter species that may be a commensal in the healthy human gut. Saliva and faeces from 20 healthy individuals were examined by PCR assays specific for nine species of campylobacter (C. sputorum, C. concisus, C. upsaliensis, C. helveticus, C. lari, C. fetus, C. hyointestinalis, C. jejuni and C. coli) and for the genus as a whole. Genus-specific amplicons were produced from 19 of 20 saliva samples and from 18 of 20 faecal samples. C. concisus species-specific amplicons were produced from 19 of 20 saliva samples and 3 of 20 faecal samples. The faecal samples were all PCR-negative for other Campylobacter species. Three unidentified 16S rRNA Campylobacter genus-specific amplicons of faecal origin were sequenced. Phylogenetic analysis showed that these sequences were 99% similar, and clustered within the genus as a novel group which was termed HS (HS = healthy subject). A PCR primer pair specific for the HS group was designed from the sequence data and used to reexamine the original samples. Although it was not possible to culture the organism from faeces, specific PCR assay detected it in 10 of the 20 faecal samples, but not in any corresponding saliva samples. The authors propose that the source of the amplicons is a previously undescribed and so far uncultivated species, which they term 'Candidatus Campylobacter hominis'.

Adolescent↗