Generation of miRNA sponge constructs. TibidyHealth : Liver #Function #Micromana... Liver Function Micromanaged By MiR-122. TibidyHealth : All about #miRNA. Tagged o... TibidyHealth : All about #mRNA. Tagged on... Interacting small RNA pathways in worms 2: 22G-RNAs. In two papers published in 2009 (Gu et al. and Claycomb et al), Craig Mello’s group characterised 22G-RNAs. They found that they could be divided into two different functional classes based on the Argonaute proteins with which they are complexed – CSR-1 or WAGOs. The biogenesis of both groups utilises common factors, but each targets different classes of loci and fulfil different roles. The starting point for the discovery of 22G-RNAs was the analysis of various mutant alleles of the gene drh-3 (which encodes a dicer-related helicase).
Homozygous drh-3 alleles result in infertile worms, whilst RNAi targeting leads to worms dying in embryogenesis with defects in chromosome segregation and in the production of small RNA populations. Gu et al identified three partial loss of function drh-3 alleles in which the homozygous worms were viable at 20°C but infertile at 25°C. By analysing various mutant lines, Gu et al. found that 22G-RNAs are present in the soma and the germline. Like this: ScienceIndex_ : The C... TibidyHealth : Liver Cancer Could Be Due... ScienceIndex_ : RNAi:... RNAi: Future in Insect Management. ScienceIndex_ : Estim... ScienceIndex_ : Squar... SciReports: Position-dependent FUS-RNA... ScienceIndex_ : Gener... Interacting small RNA pathways in worms 3: CSR-1 associated 22G-RNAs. Anaphase during the first mitosis of a C. elegans embryo. Microtubules (green) are pulling the two sets of daughter chromosomes (blue) towards the centrosomes (yellow).
During mitosis, duplicated chromosomes are separated and segregated into two daughter cells. This is achieved by the action of spindle microtubules. In metaphase, microtubules radiating from centrosomes at two poles in the cell, attach to the condensed chromosomes at proteinaceous structures called kinetochores. The daughter chromosomes are then pulled slowly towards opposite poles during anaphase. An important feature of the mechanisms stabilising the heterochromatic state in some organisms are small RNAs. Not all organisms’ chromosomes contain single centromeres.
In C. elegans, a number of mutations affecting components of RNAi pathways were found to cause mitotic and meiotic chromosome segregation defects. In embryos depleted of any of these factors, chromosomes initially condense normally in prophase. Like this: Leclercfl : Nanomovie 1 Nanomovie 1 Th... Leclercfl : 3D tRNA molecule 3D tRNA m... ScienceIndex_ : Valid... ScienceIndex_ : A rev... ScienceIndex_ : The h... Epistasis between mutations is host-dependent for an RNA virus « Tracing Knowledge … Στα ίχνη της Γνώσης.
Epistasis between mutations is host-dependent for an RNA virus Jasna Lalić1 and Santiago F. Elena1,2,**Author for correspondence (santiago.elena@csic.es). Abstract How, and to what extent, does the environment influence the way mutations interact? Do environmental changes affect both the sign and the magnitude of epistasis? 1. The large majority of emerging viruses are RNA viruses [1]. To evaluate the effect that different hosts exert on the distribution of epistatic interactions, we tested the fitness of Tobacco etch virus (TEV) genotypes carrying two single-nucleotide substitutions, whose independent effects were previously evaluated [6], across susceptible hosts of increasing genetic divergence from the primary host.
Continue Reading Here Jasna Lalić, & Santiago F. Tracing Knowledge Notification | Ειδοποίηση Στα ίχνη της Γνώσης UNMODIFIED COPYof the original post, out of respect to the source and readers.Please follow the link for references and more informations. Like this: Related. Spongelab: Transcription Hero is an e... Plant biology: Current Biology 'RNA-Direc... Anything DNA Can Do … Fixing mitochindrial mutations with targeted mitochondrial RNA import. If you've been reading the blog for a while now, you've heard this many times: not all mutations are deleterious, but the ones that are can increase the risk of certain cancers and diseases. Numerous genetic defects have been attributed to mutations, and mutation in the mtDNA, the mitochondrial DNA, are no exceptions: "Specific mutations in mtDNA have been implicated in muscular and neuronal disease and in the decline of organ function with aging. Despite a significant need, there are currently no effective treatments for mtDNA alterations [1]".
I've often talked about gene therapy as a way to try and fix defects caused by genetic mutations. The idea behind gene therapy is to introduce the non-mutated gene into the cells so that the production of the healthy protein can be restored. So, a natural question to ask would be: can we use gene therapy to fix mtDNA mutations as well? In their March PNAS paper, Wang et al. note: Tibidy Health: Major Breakthrough In Macu... Plant biology: Free in Current Biology 'I... Patterns of RNA methylation. A new paper in Cell provides a transcriptome-wide survey of the methylation of adenosine residues in RNAs.
Meyer et al find that this epitranscriptomic post-transcriptional modification is widespread and dynamically regulated, and likely to play important roles in cellular regulation. Methylation of the N6 position of adenosine residues (m6A) has been known to be a post-transcriptional modification of RNAs for many years. Research in the 1960’s and 70’s demonstrated that m6A is present in tRNAs, rRNAs and viral RNAs, and made up between 0.1% and 0.4% or total adenosines in cellular RNA. However as m6A was not easily detectable by commonly available methods, research on this modified base foundered. A recent spur to experimentation on m6A has come from the analysis of a gene linked to obesity. FTO (fat mass and obesity associated) is a major regulator of metabolism and energy utilisation.
Meyer, K., Saletore, Y., Zumbo, P., Elemento, O., Mason, C., & Jaffrey, S. (2012). Like this: RNA breakthrough transforms idea of gene control - health - 18 May 2012. Tiny chemical changes that do not alter the sequence of our DNA but modulate how it works have been found to act on a new part of our genetic machinery. The discovery could provide insights into many health problems, including obesity. It has been long known that DNA can be altered "epigenetically" – where changes occur without altering the sequence of DNA but leave chemical marks on genes that dictate how active they are by adding chemical methyl groups that silence genes, for example. Numerous environmental factors, such as stress and smoking, have been shown to influence these epigenetic marks.
Now, researchers have discovered that messenger RNA, the mirror-image copy of DNA from which all proteins are manufactured, can be methylated too. "We've discovered something fundamental to biology," says Samie Jaffrey of Cornell University in New York, and head of the team that made the discovery. "It was there all the time and no-one knew about it. " Fundamental discovery More From New Scientist. UK PubMed Central: MRC: Piwi and piRNAs Act U... Rna-silencing. PLoSPathogens : Exploring the interactions... Inferring DNA from RNA. A new technique to derive DNA information from non-DNA sources, such as RNA, threatens the anonymity of genetic database donors. Your DNA sequence may not be as secure as you think.
DNA databases contain hordes of information about people’s genetic makeup, including mutations that may put them at higher risks of certain diseases and, more generally, a genetic barcode that is unique to each individual. For this reason, access to such data is restricted to protect identity and health information. RNA data, on the other hand, reside in publicly available databases, which house results of thousands of genomic studies from the last several years.
Now, Eric E. “We need to accept the reality that it is difficult—if not impossible—to shield personal information from others,” Schadt said in a press release. The National Institutes of Health (NIH), which hosts one of the largest DNA databases, is not concerned, however, ScienceInsider reported. 3-D RNA Modeling Opens Scientific Doors. In a paper published in the journal Nature Methods, a team from the University of North Carolina at Chapel Hill demonstrates a simple, cost-effective technique for three-dimensional RNA structure prediction that will help scientists understand the structures, and ultimately the functions, of the RNA molecules that dictate almost every aspect of human cell behavior. When cell behavior goes wrong, diseases - including cancer and metabolic disorders - can be the result... carolina chapel function hill nature north prediction rna scientists university oxo Remove a tag from the tag selection xox Keep a tag in the selection and remove others Scientists at the University of North Carolina at Chapel Hill have identified a new way to deliver long-lasting pain relief through an ancient medical practice.
Carolina chapel hill mark mechanism north papupuncture practice scientists treatment unc university carolina chapel hill north practice scientists university. Tibidy Health: Mod5 yeast prion contribut... A dual purpose RNA and Hox regulation. A new paper in Plos Genetics shows that a long non-coding RNA regulates the expression of a Hox gene in Drosophila in cis. This finding suggests an explanation for the co-linearity displayed by Hox genes between genomic arrangement and expression pattern. The Ultrabithorax mutant. Hox genes are master-regulators of positional identity along the anterior-posterior axis throughout bilaterian animals.
Hox genes are found in genomic clusters in which their 3′-5′ organisation mirrors their expression pattern along the A-P axis. This correspondence between body axis and genomic organisation is termed co-linearity. An important feature of Hox gene genetics is the phenomenon of ‘posterior prevalence’. The Hox gene cluster is actually divided into two partial clusters in Drosophila; the Antennapedia complex (ANT-C) and the Bithorax complex (BX-C). Figure showing the expression of ABD-A (red), and ABD-B (green) in the embryonic CNS. Like this: Like Loading... The cell's 'New World': First complete atlas of RNA-binding proteins. In one of the most famous faux pas of exploration, Columbus set sail for India and instead 'discovered' America. Similarly, when scientists at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, set out to find enzymes – the proteins that carry out chemical reactions inside cells – that bind to RNA, they too found more than they expected: 300 proteins previously unknown to bind to RNA – more than half as many as were already known to do so.
The study, published online today in Cell, could help to explain the role of genes that have been linked to diseases like diabetes and glaucoma. "We are very excited that, unlike Columbus, we found what we were looking for: well-known enzymes that bind to RNA," says Matthias Hentze, who led the study at EMBL with Jeroen Krijgsveld. "But we never thought there was still so much unexplored territory, so many of these RNA-binding proteins to be discovered.
" Plantbiology : Free in Plant Cell 'DEXH B... Chemical substitution: On early Earth, iron may have performed magnesium's RNA folding job. On the periodic table of the elements, iron and magnesium are far apart. But new evidence suggests that 3 billion years ago, iron did the chemical work now done by magnesium in helping RNA fold and function properly.
There is considerable evidence that the evolution of life passed through an early stage when RNA played a more central role before DNA and coded proteins appeared. During that time, more than 3 billion years ago, the environment lacked oxygen but had an abundance of soluble iron. In a new study, researchers from the Georgia Institute of Technology used experiments and numerical calculations to show that iron, in the absence of oxygen, can substitute for magnesium in RNA binding, folding and catalysis. The researchers found that RNA's shape and folding structure remained the same and its functional activity increased when magnesium was replaced by iron in an oxygen-free environment. The results of the study were published online on May 31, 2012 in the journal PLoS ONE. Sciencemagazine: Inside Argonaute2, core pr... This Week in Genome Research.
On early Earth, iron may have performed magnesium's RNA folding job. On the periodic table of the elements, iron and magnesium are far apart. But new evidence suggests that 3 billion years ago, iron did the chemical work now done by magnesium in helping RNA fold and function properly. There is considerable evidence that the evolution of life passed through an early stage when RNA played a more central role before DNA and coded proteins appeared. During that time, more than 3 billion years ago, the environment lacked oxygen but had an abundance of soluble iron. In a new study, researchers from the Georgia Institute of Technology used experiments and numerical calculations to show that iron, in the absence of oxygen, can substitute for magnesium in RNA binding, folding and catalysis.
The results of the study were published online on May 31, 2012 in the journal PLoS ONE. Free oxygen gas was almost nonexistent more than 3 billion years ago in the early earth's atmosphere. Explore further: How a Silly Putty ingredient could advance stem cell therapies. Real-time monitoring of RNA splicing in living cells moves step closer with novel fluorescent probe. Numerous biological processes depend on molecules called lariat RNAs (LaRNAs). These lasso-shaped structures form in the cell during RNA splicing. During this process, transcribed RNA strands convert to messenger RNA before undergoing translation into proteins. A way to quickly and efficiently characterize these molecules in living cells is now available, thanks to a method developed by a research team led by Hiroshi Abe of the RIKEN Advanced Science Institute, Wako.
The method identifies LaRNAs using molecular pairs called reduction-triggered fluorescent (REFT) probes. In contrast to earlier approaches to identify elusive LaRNAs, Abe and his team adopted a simple, non-enzymatic strategy. Performance assessments using these probe-linked DNA strands, which could bind different portions of the LaRNAs, showed that a fluorescent signal was emitted only when the reacting components could access the target at the lasso junction.
More information: Furukawa, K., et al. FurnoX: Site-specific DICER and DR... New exception to a decades-old rule about RNA splicing uncovered. There are always exceptions to a rule, even one that has prevailed for more than three decades, as demonstrated by a Cold Spring Harbor Laboratory (CSHL) study on RNA splicing, a cellular editing process. The rule-flaunting exception uncovered by the study concerns the way in which a newly produced RNA molecule is cut and pasted at precise locations called splice sites before being translated into protein. "The discovery of this exception could impact current ideas on how missteps in splicing triggered by mutations in the DNA sequence can lead to diseases such as cancer and various genetic disorders," says CSHL Professor Adrian Krainer, Ph.D., who led the research. The study appears in the May 15 issue of Genes & Development. For a protein to be synthesized by the cell, the instructions encoded within that protein's gene have to be first copied from DNA into RNA.
Krainer and Roca have now found a second, and much more prevalent, alternative option. Research uncovers new exception to decades-old rule about RNA splicing. There are always exceptions to a rule, even one that has prevailed for more than three decades, as demonstrated by a Cold Spring Harbor Laboratory (CSHL) study on RNA splicing, a cellular editing process. The rule-flaunting exception uncovered by the study concerns the way in which a newly produced RNA molecule is cut and pasted at precise locations called splice sites before being translated into protein.
"The discovery of this exception could impact current ideas on how missteps in splicing triggered by mutations in the DNA sequence can lead to diseases such as cancer and various genetic disorders," says CSHL Professor Adrian Krainer, Ph.D., who led the research. The study appears in the May 15 issue of Genes & Development. For a protein to be synthesized by the cell, the instructions encoded within that protein's gene have to be first copied from DNA into RNA.
Krainer and Roca have now found a second, and much more prevalent, alternative option. RNA modification influences thousands of genes: Revolutionizes understanding of gene expression. Researchers reveal an RNA modification influences thousands of genes. Novel RNA transport mechanism: Ribonucleoprotein granules exit the nucleus via a budding mechanism.
Henry Furneaux Ph.D.: A Long ncRNA Links Copy Nu... Plant biology: Current Biology 'Involveme... Targeted Delivery of PLK1-siRNA by ScFv Suppresses Her2+ Breast Cancer Growth and Metastasis. Silencing of the Genes. Silencing Genes in HIV. Shutting the Door on HIV. All proteins that bind to RNA, including 300 new ones, catalogued. Researchers achieve RNA interference, in a lighter package. Researchers achieve RNA interference, in a lighter package. RNA study finds activity in silent regions of human genome. Rewriting the Rules for RNA Interference. MicrobeWorld: RNA studies under fire: Hi... Tibidy Health: #RNAi, #MiRNA & #SiRNA: A... HealthyTweet: Health News Tweet RNAi, Mi... Genomigence: NAR: {beta}-Catenin recogn... Sharmanedit : RT @Alexbateman1: So that'...
This Week in Cell. Adding iron is like giving early RNA enzymes “steroids” GNN’S NEWS BY TOPIC - RNA Interference (Gene Silencing) RNA-binding proteins accumulate in the brains of patients with AD. TibidyHealth : All about RNA-binding. Tag... Plantbiology : PNAS 'Regulation of miRNA... OxfordJournals : RT @dullhunk: Lovely visua... SciReports: Single-Molecule Electrical... Targeting double-stranded RNA dependent protein kinase could treat inflammation. FurnoX : Chimeras taking shape: Pot... Small RNA in the Spotlight. FurnoX: RT @Jen_Angela: RNA-progra... PLoSPathogens : How Do Viruses Interact wi... Science Magazine: Sign In. Science Magazine: Sign In. Science Magazine: Sign In. Patterns of RNA methylation 2.
New role for RNAi discovered: Epigenetic memory may pass RNA silencing from one generation to the next. XNA is synthetic DNA that's stronger than the real thing. Plantbiology : PNAS 'Antisilencing role o... SciReports : Involvement of RDR6 in sho... Cytoplasmic RNA-Binding Proteins and the Control of Complex Brain Function. Biochemists map structure of key protein-RNA complex required for assembly of telomerase. Lariats: How RNA Splicing Decisions are Made. BioMedCentral: #Molecular dynamics simula... BMC_series : #Molecular dynamics simula... BioMedCentral: RT @BMC_series: New resear... BMC_series : New research on #RNA polym... Lariats: How RNA splicing decisions are made. Lariats: How RNA splicing decisions are made. TibidyHealth : RNA-binding proteins accum... Between Genes and Proteins. RNA Stair at the National Academies. A repeated case: Expansions in RNA cause myotonic dystrophy.