712 research outputs found
Noncoding RNAs database (ncRNAdb)
The noncoding RNA database (ncRNAdb) was created as a source of information on RNA molecules, which do not possess protein-coding capacity. It is now widely accepted that, in addition to constitutively expressed, housekeeping or infrastructural RNAs, there is a wide variety of RNAs participating in mechanisms involved in regulation of gene expression at all levels of transmission of genetic information from DNA to proteins. Noncoding RNAs' activities include chromatin structure remodeling, transcriptional and translational regulation of gene expression, modulation of protein function and regulation of subcellular distribution of RNAs as well as proteins. Noncoding transcripts have been identified in organisms belonging to all domains of life. Currently, the ncRNAdb contains >30 000 ncRNA sequences from Eukaryotes, Eubacteria and Archaea, but does not include housekeeping transcripts or microRNAs and snoRNAs for which more specialized databases are available. The contents of the database can be accessed via the WWW at
A photometric and spectroscopic study of WW And - an Algol-type, long period binary system with an accretion disc
We have analyzed the available spectra of WW And and for the first time
obtained a reasonably well defined radial velocity curve of the primary star.
Combined with the available radial velocity curve of the secondary component,
these data led to the first determination of the spectroscopic mass ratio of
the system at q-spec = 0.16 +/- 0.03. We also determined the radius of the
accretion disc from analysis of the double-peaked H-alpha emission lines. Our
new, high-precision, Johnson VRI and the previously available Stromgren vby
light curves were modelled with stellar and accretion disc models. A consistent
model for WW And - a semidetached system harbouring an accretion disc which is
optically thick in its inner region, but optically thin in the outer parts -
agrees well with both spectroscopic and photometric data.Comment: Accepted by New Astronom
5SRNAdb: an information resource for 5S ribosomal RNAs
Ribosomal 5S RNA (5S rRNA) is the ubiquitous RNA component found in the large
subunit of ribosomes in all known organisms. Due to its small size, abundance
and evolutionary conservation 5S rRNA for many years now is used as a model
molecule in studies on RNA structure, RNA–protein interactions and molecular
phylogeny. 5SRNAdb (http://combio.pl/5srnadb/) is the first database that
provides a high quality reference set of ribosomal 5S RNAs (5S rRNA) across
three domains of life. Here, we give an overview of new developments in the
database and associated web tools since 2002, including updates to database
content, curation processes and user web interfaces
Recommended from our members
Organelle trafficking of chimeric ribozymes and genetic manipulation of mitochondria
With the expansion of the RNA world, antisense strategies have become widespread to manipulate nuclear gene expression but organelle genetic systems have remained aside. The present work opens the field to mitochondria. We demonstrate that customized RNAs expressed from a nuclear transgene and driven by a transfer RNA-like (tRNA-like) moiety are taken up by mitochondria in plant cells. The process appears to follow the natural tRNA import specificity, suggesting that translocation indeed occurs through the regular tRNA uptake pathway. Upon validation of the strategy with a reporter sequence, we developed a chimeric catalytic RNA composed of a specially designed trans-cleaving hammerhead ribozyme and a tRNA mimic. Organelle import of the chimeric ribozyme and specific target cleavage within mitochondria were demonstrated in transgenic tobacco cell cultures and Arabidopsis thaliana plants, providing the first directed knockdown of a mitochondrial RNA in a multicellular eukaryote. Further observations point to mitochondrial messenger RNA control mechanisms related to the plant developmental stage and culture conditions. Transformation of mitochondria is only accessible in yeast and in the unicellular alga Chlamydomonas. Based on the widespread tRNA import pathway, our data thus make a breakthrough for direct investigation and manipulation of mitochondrial genetics
Succinate Dehydrogenase-Deficient Renal Cancer Featuring Fructose-1,6-Biphosphatase Loss, Pyruvate Kinase M2 Overexpression, and SWI/SNF Chromatin Remodeling Complex Aberrations: A Rare Case Report
Succinate dehydrogenase (SDH)-deficient renal cancer is
a rare renal cancer subtype recently accepted by the
World Health Organization as a unique subtype of renal
cell carcinoma (RCC). Here we report a case of 17-year old man. The detailed evaluation indicated occurrence
of the SDHB-deficient RCC. The genetic testing revealed
no germline mutation in SDH genes. Immunohistochemistry showed SDHB deficiency, overexpression of pyruvate kinase M2 and dramatic downregulation of
fructose-1,6-bisphosphatase metabolic enzymes, and
unaltered levels of phosphorylated AMP-activated
protein kinase and mammalian target of rapamycin.
Strong upregulation of INI1 and BRG1 and overexpression of BAF180, subunits of SWI/SNF ATP-dependent chromatin remodeling complex, were also
found. The identified tumor pathologically did not
resemble clear cell renal cell carcinoma (ccRCC), but
some metabolic alterations are common for both cancer
types. Thus, we postulate that the phenotypical differences between ccRCC and SDHB-deficient RCC may be
related to distinct molecular and metabolic alterations
Organelle trafficking of chimeric ribozymes and genetic manipulation of mitochondria
With the expansion of the RNA world, antisense strategies have become widespread to manipulate nuclear gene expression but organelle genetic systems have remained aside. The present work opens the field to mitochondria. We demonstrate that customized RNAs expressed from a nuclear transgene and driven by a transfer RNA-like (tRNA-like) moiety are taken up by mitochondria in plant cells. The process appears to follow the natural tRNA import specificity, suggesting that translocation indeed occurs through the regular tRNA uptake pathway. Upon validation of the strategy with a reporter sequence, we developed a chimeric catalytic RNA composed of a specially designed trans-cleaving hammerhead ribozyme and a tRNA mimic. Organelle import of the chimeric ribozyme and specific target cleavage within mitochondria were demonstrated in transgenic tobacco cell cultures and Arabidopsis thaliana plants, providing the first directed knockdown of a mitochondrial RNA in a multicellular eukaryote. Further observations point to mitochondrial messenger RNA control mechanisms related to the plant developmental stage and culture conditions. Transformation of mitochondria is only accessible in yeast and in the unicellular alga Chlamydomonas. Based on the widespread tRNA import pathway, our data thus make a breakthrough for direct investigation and manipulation of mitochondrial genetics
RNAcentral 2021: secondary structure integration, improved sequence search and new member databases
RNAcentral is a comprehensive database of non-coding RNA (ncRNA) sequences that provides a single access point to 44 RNA resources and >18 million ncRNA sequences from a wide range of organisms and RNA types. RNAcentral now also includes secondary (2D) structure information for >13 million sequences, making RNAcentral the world's largest RNA 2D structure database. The 2D diagrams are displayed using R2DT, a new 2D structure visualization method that uses consistent, reproducible and recognizable layouts for related RNAs. The sequence similarity search has been updated with a faster interface featuring facets for filtering search results by RNA type, organism, source database or any keyword. This sequence search tool is available as a reusable web component, and has been integrated into several RNAcentral member databases, including Rfam, miRBase and snoDB. To allow for a more fine-grained assignment of RNA types and subtypes, all RNAcentral sequences have been annotated with Sequence Ontology terms. The RNAcentral database continues to grow and provide a central data resource for the RNA community
RNAcentral 2021: secondary structure integration, improved sequence search and new member databases.
RNAcentral is a comprehensive database of non-coding RNA (ncRNA) sequences that provides a single access point to 44 RNA resources and >18 million ncRNA sequences from a wide range of organisms and RNA types. RNAcentral now also includes secondary (2D) structure information for >13 million sequences, making RNAcentral the world's largest RNA 2D structure database. The 2D diagrams are displayed using R2DT, a new 2D structure visualization method that uses consistent, reproducible and recognizable layouts for related RNAs. The sequence similarity search has been updated with a faster interface featuring facets for filtering search results by RNA type, organism, source database or any keyword. This sequence search tool is available as a reusable web component, and has been integrated into several RNAcentral member databases, including Rfam, miRBase and snoDB. To allow for a more fine-grained assignment of RNA types and subtypes, all RNAcentral sequences have been annotated with Sequence Ontology terms. The RNAcentral database continues to grow and provide a central data resource for the RNA community. RNAcentral is freely available at https://rnacentral.org
RNAcentral : a hub of information for non-coding RNA sequences
RNAcentral is a comprehensive database of non-coding RNA (ncRNA) sequences, collating information on ncRNA sequences of all types from a broad range of organisms. We have recently added a new genome mapping pipeline that identifies genomic locations for ncRNA sequences in 296 species. We have also added several new types of functional annotations, such as tRNA secondary structures, Gene Ontology annotations, and miRNA-target interactions. A new quality control mechanism based on Rfam family assignments identifies potential contamination, incomplete sequences, and more. The RNAcentral database has become a vital component of many workflows in the RNA community, serving as both the primary source of sequence data for academic and commercial groups, as well as a source of stable accessions for the annotation of genomic and functional features. These examples are facilitated by an improved RNAcentral web interface, which features an updated genome browser, a new sequence feature viewer, and improved text search functionality. RNAcentral is freely available at https://rnacentral.org
Copy number variation of microRNA genes in the human genome
<p>Abstract</p> <p>Background</p> <p>MicroRNAs (miRNAs) are important genetic elements that regulate the expression of thousands of human genes. Polymorphisms affecting miRNA biogenesis, dosage and target recognition may represent potentially functional variants. The functional consequences of single nucleotide polymorphisms (SNPs) within critical miRNA sequences and outside of miRNA genes were previously demonstrated using both experimental and computational methods. However, little is known about how copy number variations (CNVs) affect miRNA genes.</p> <p>Results</p> <p>In this study, we analyzed the co-localization of all miRNA <it>loci </it>with known CNV regions. Using bioinformatic tools we identified and validated 209 copy number variable miRNA genes (CNV-miRNAs) in CNV regions deposited in Database of Genomic Variations (DGV) and 11 CNV-miRNAs in two sets of CNVs defined as highly polymorphic. We propose potential mechanisms of CNV-mediated variation of functional copies of miRNAs (dosage) for different types of CNVs overlapping miRNA genes. We also showed that, consistent with their essential biological functions, miRNA <it>loci </it>are underrepresented in highly polymorphic and well-validated CNV regions.</p> <p>Conclusion</p> <p>We postulate that CNV-miRNAs are potential functional variants and should be considered high priority candidate variants in genotype-phenotype association studies.</p
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