Hairpin turn: Micro-RNA plays role in wood formation. For more than a decade, scientists have suspected that hairpin-shaped chains of micro-RNA regulate wood formation inside plant cells. Now, scientists at NC State University have found the first example and mapped out key relationships that control the process. The research, published online in Proceedings of the National Academy of Sciences the week of June 10, describes how one strand of micro-RNA reduced by more than 20 percent the formation of lignin, which gives wood its strength. Understanding how to reduce lignin at the cellular level could lead to advances in paper and biofuels production, where harsh chemicals and costly treatments are used to remove lignin from wood.
"This is the first time that we have proof that a micro-RNA controls lignin biosynthesis," said Dr. Vincent Chiang, who co-directs NC State's Forest Biotechnology Group with Dr. Ron Sederoff, a member of the National Academy of Sciences. Lead authors are Dr. Helping RNA escape from cells' recycling process could make it easier to shut off disease-causing genes. Nanoparticles that deliver short strands of RNA offer a way to treat cancer and other diseases by shutting off malfunctioning genes. Although this approach has shown some promise, scientists are still not sure exactly what happens to the nanoparticles once they get inside their target cells. A new study from MIT sheds light on the nanoparticles' fate and suggests new ways to maximize delivery of the RNA strands they are carrying, known as short interfering RNA (siRNA). "We've been able to develop nanoparticles that can deliver payloads into cells, but we didn't really understand how they do it," says Daniel Anderson, the Samuel Goldblith Associate Professor of Chemical Engineering at MIT.
"Once you know how it works, there's potential that you can tinker with the system and make it work better. " Through a process called RNA interference, siRNA targets messenger RNA (mRNA), which carries genetic instructions from a cell's DNA to the rest of the cell. Molecular traffic jam. DNA found outside genes plays largely unknown, potentially vital roles: Thousands of previously unknown RNA molecules identified. A new UC San Francisco study highlights the potential importance of the vast majority of human DNA that lies outside of genes within the cell. The researchers found that about 85 percent of these stretches of DNA make RNA, a molecule that increasingly is being found to play important roles within cells. They also determined that this RNA-making DNA is more likely than other non-gene DNA regions to be associated with inherited disease risks. The study, published in the free online journal PLOS Genetics on June 20, 2013, is one of the most extensive examinations of the human genome ever undertaken to see which stretches of DNA outside of genes make RNA and which do not.
The researchers -- senior author and RNA expert Michael McManus, PhD, UCSF associate professor of microbiology and immunology and a member of the UCSF Diabetes Center, graduate student Ian Vaughn, and postdoctoral fellow Matthew Hangauer, PhD -- identified thousands of previously unknown, unique RNA sequences. Tiny RNA molecules could have medical applications. A team led by scientists at The Scripps Research Institute (TSRI) has identified a family of tiny RNA molecules that work as powerful regulators of the immune response in mammals.
Mice who lack these RNA molecules lose their normal infection-fighting ability, whereas mice that overproduce them develop a fatal autoimmune syndrome. "This finding gives us insights into immune regulation that could be very helpful in a range of medical applications, from viral vaccines to treatments for autoimmune diseases," said Changchun Xiao, assistant professor in TSRI's Department of Immunology and Microbial Science and senior investigator for the study, which appears in the June 30, 2013 issue of Nature Immunology. Unraveling a Crucial Process The finding concerns a key interaction between T cells and B cells, the allied lymphocyte armies that make up most of the adaptive immune system of mammals. Surprising Finding Important Targets. Researcher sheds light on M.O. of unusual RNA molecules.
The genes that code for proteins -- more than 20,000 in total -- make up only about 1 percent of the complete human genome. That entire thing -- not just the genes, but also genetic junk and all the rest -- is coiled and folded up in any number of ways within the nucleus of each of our cells. Think, then, of the challenge that a protein or other molecule, like RNA, faces when searching through that material to locate a target gene.
Now a team of researchers led by newly arrived biologist Mitchell Guttman of the California Institute of Technology (Caltech) and Kathrin Plath of UCLA, has figured out how some RNA molecules take advantage of their position within the three-dimensional mishmash of genomic material to home in on targets. The research appears in the current issue of Science Express. The findings suggests a unique role for a class of RNAs, called lncRNAs, which Guttman and his colleagues at the Broad Institute of MIT and Harvard first characterized in 2009. It slices, it dices, it silences: ADAR1 as gene-silencing modular RNA multitool. RNA, once considered a bit player in the grand scheme by which genes encode protein, is increasingly seen to have a major role in human genetics.
In a study presented in the April 25 issue of the journal Cell, researchers from The Wistar Institute discovered how the RNA-editing protein, ADAR1, also combines with the protein called Dicer to create microRNA (miRNA) and small interfering (siRNA). These varieties of RNA, in turn, play a crucial role in gene regulation--silencing or "switching off" the production of specific proteins. Upward of 60 percent of mammalian genes are thought to be targeted and regulated by non-coding RNA molecules, researchers say.
This aspect of RNA biology is so critical to life, in fact, that the Nishikura laboratory demonstrated how a lack of ADAR1 was lethal in embryonic mice. The genome, in the form of DNA, contains the instructions for both new proteins and the RNA that helps regulate how protein production is controlled. Big data analysis identifies prognostic RNA markers in a common form of breast cancer. A Big-Data analysis that integrates three large sets of genomic data available through The Cancer Genome Atlas has identified 37 RNA molecules that might predict survival in patients with the most common form of breast cancer. The study by researchers at the Ohio State University Comprehensive Cancer Center -- Arthur G. James Cancer Hospital and Richard J.
Solove Research Institute (OSUCCC -- James) initially analyzed messenger RNA (mRNA) and microRNA expression, DNA methylation data and clinical findings for 466 patients with invasive ductal carcinoma, the most common type of breast cancer. The analysis identified 30 mRNAs and seven microRNAs -- short snippets of RNA -- that were consistently associated with patient outcome across 44 clinical and molecular subclasses, including early-stage tumors.
"This is the first prognostic signature in breast cancer or other type of cancer that combines both mRNA and microRNA," says first author and researcher Dr. Principal investigator Dr. RNA interference drug demonstrated activity and safety in phase I trial. Apr. 9, 2013 — Early results from a phase I, first in-human study indicate that a potential new class of drugs, RNA interference (RNAi) drugs, can be safely administered in humans, according to a researcher who presented data on the safety and preliminary efficacy of TKM-080301 at the AACR Annual Meeting 2013, held in Washington, D.C., April 6-10. TKM-080301, also known as TKM-PLK1, is an RNAi drug being developed by Tekmira Pharmaceuticals Corporation. "RNAi therapies are a unique approach to cancer treatment as they have the potential to 'turn off' the genes' coding for proteins involved in cancer cell division," said Ramesh K.
Ramanathan, M.D., medical director of the Virginia G. Piper Cancer Center Clinical Trials Program at Scottsdale Healthcare and deputy director of the Clinical Translational Research Division of the Translational Genomics Research Institute (TGen) in Phoenix, Ariz. Share this story on Facebook , Twitter , and Google : Other social bookmarking and sharing tools: Tiny RNA molecule may have role in polycystic ovary syndrome, insulin resistance.
A group of tiny RNA molecules with a big role in regulating gene expression also appear to have a role in causing insulin resistance in woman with polycystic ovary syndrome and, perhaps, in all women, researchers report. Research in the journal Diabetes, indicates that high activity levels of a microRNA called miR-93 in fat cells impedes insulin's use of glucose, contributing to PCOS as well as insulin resistance, said Dr. Ricardo Azziz, reproductive endocrinologist and PCOS expert at the Medical College of Georgia at Georgia Regents University. "This is one of the first reports of a defect that may occur both in women who are insulin resistant and, in particular, in women with PCOS," said Azziz, the study's corresponding author. "Identifying this molecular mechanism helps us understand these common conditions better and points us toward targeted therapies to correct these problems in women.
" Researchers looked at fat cells from the lower abdomen of 21 women with PCOS and 20 controls. Tiny piece of RNA keeps 'clock' running in earliest stages of life. New research shows that a tiny piece of RNA has an essential role in ensuring that embryonic tissue segments form properly. The study, conducted in chicken embryos, determined that this piece of RNA regulates cyclical gene activity that defines the timing of the formation of tissue segments that later become muscle and vertebrae.
Genes involved in this activity are turned on and off in an oscillating pattern that matches the formation of each tissue segment. If the timing of these genes' activity doesn't remain tightly regulated, the tissue either won't form at all or will form with defects. One gene long associated with this segmentation "clock" is called Lfng. Researchers established in this study that a single microRNA -- a tiny segment of RNA that has no role in producing any protein -- is key to turning off Lfng at precisely the right time as tissues form in this oscillating pattern.
The research is published in the journal Developmental Cell. 'Activating' RNA takes DNA on a loop through time and space. Long segments of RNA -- encoded in our DNA but not translated into protein -- are key to physically manipulating DNA in order to activate certain genes. These non-coding RNA-activators (ncRNA-a) have a crucial role in turning genes on and off during early embryonic development, researchers say, and have also been connected with diseases, including some cancers, in adults.
In an online article of the journal Nature, a team of scientists led by Wistar's Ramin Shiekhattar, Ph.D., detail the mechanism by which long non-coding RNA-activators promote gene expression. They show how these RNA molecules help proteins in the cell to create a loop of DNA in order to open up genes for transcription. Their experiments have also described how particular ncRNA-a molecules are related to FG syndrome, a genetic disease linked to severe neurological and physical deficits. Deep genomic analysis identifies a micro RNA opponent for ovarian cancer.
Researchers employed an extensive analysis of genomic information to identify a new, high-risk cohort of ovarian cancer patients, characterize their tumors, find a potential treatment and test it in mouse models of the disease. The exhaustive analysis that led to micro RNA 506 (miR-506) as a potential therapeutic candidate for advanced or metastatic ovarian cancer is the cover article in the Feb. 11 edition of Cancer Cell.
"Functional analysis showed that miR-506 is a robust inhibitor of a cellular transition that makes ovarian cancer cells more resistant to treatment and likely to spread. We will continue to investigate this micro RNA as an inhibitor of ovarian cancer metastasis," said Wei Zhang, Ph.D. professor in MD Anderson's Department of Pathology and senior author of the paper. Micro RNAs do not code for genes like their cousins, the messenger RNAs. Analysis of human tumors showed higher miR-506 expression is associated with longer overall survival. RNA promotes metastasis in lung cancer. MALAT1, an RNA molecule, is a marker for progression of lung cancer.
Heidelberg researchers have now found out that MALAT1 activates metastasis-promoting genes in cancer cells. In mice, blocking of MALAT1 reduced the number and size of lung cancer metastases. The vast majority -- approximately 80 percent -- of our DNA does not code for proteins, yet it gets transcribed into RNA. These RNA molecules are called non-coding and fulfill multiple tasks in the cell. Alongside a well-studied group of small RNAs, there is also a class of so-called long non-coding RNAs consisting of more than 200 nucleotides.
Long non-coding RNAs regulate cellular processes such as cell cycle, growth and cell death. In his current project, Diederichs has investigated the actual mechanisms used by MALAT1 to interfere in cellular processes and to promote metastasis. For the first time, Diederichs and his team have been able to achieve almost complete silencing of MALAT1 in lung cancer cell cultures. Macromolecular shredder for RNA: Researchers unravel the structure of the machinery for RNA disposal. Much in the same way as we use shredders to destroy documents that are no longer useful or that contain potentially damaging information, cells use molecular machines to degrade unwanted or defective macromolecules. Scientists of the Max Planck Institute of Biochemistry in Martinsried near Munich, Germany, have now decoded the structure and the operating mechanism of the exosome, a macromolecular machine responsible for degradation of ribonucleic acids (RNAs) in eukaryotes.
RNAs are ubiquitous and abundant molecules with multiple functions in the cell. One of their functions is, for example, to permit translation of the genomic information into proteins. The results of the studies now published in the journal Nature show that the structural architecture and the main operation mode of the exosome are conserved in all domains of life. Any errors that occur during the synthesis of RNA molecules or unwanted accumulation of RNAs can be damaging to the cell. A ubiquitous molecular shredder. New technique sheds light on RNA. When researchers sequence the RNA of cancer cells, they can compare it to normal cells and see where there is more RNA.
That can help lead them to the gene or protein that might be triggering the cancer. But other than spotting a few known instigators, what does it mean? Is there more RNA because it's synthesizing too quickly or because it's not degrading fast enough? What part of the biological equilibrium is off? After more than a decade of work, researchers at the University of Michigan Comprehensive Cancer Center have developed a technique to help answer those questions. The method involves a compound called bromouridine, which can be used to tag or label newly created RNA.
On the other hand, the researchers can follow up the bromouridine labeling with a rinse with the chemical uridine for different periods of time. "We can see the whole pattern of all the RNA that's synthesized and all the RNA that's stable vs. degrading. Understanding the cellular patterns of development: Key mechanism in development involves 'paused' RNA polymerase.
Class of RNA molecules protects germ cells from damage. New portable device enables RNA detection from ultra-small sample in only 20 minutes. Early-Earth cells modeled to show how first life forms might have packaged RNA. Screening method aids RNA drug development research. Smallest and fastest-known RNA switches provide new drug targets. Common RNA pathway found in ALS and dementia.
In obesity, a micro-RNA causes metabolic problems. Realizing the promise of RNA nanotechnology for new drug development. Using RNA nanotechnology to treat cancers and viral infections: New study shows promise. Ancient enzymes function like nanopistons to unwind RNA. To cap or not to cap: Scientists find new RNA phenomenon that challenges dogma.
Molecular code cracked: Code determines recognition of RNA molecules. What happens when we sunburn: Red is RNA damage to skin cells. New role for RNAi discovered: Epigenetic memory may pass RNA silencing from one generation to the next. Lariats: How RNA splicing decisions are made. Researchers achieve RNA interference, in a lighter package. All proteins that bind to RNA, including 300 new ones, catalogued. Chemical substitution: On early Earth, iron may have performed magnesium's RNA folding job. RNA: From messenger to guardian of genome integrity. New exception to a decades-old rule about RNA splicing uncovered. RNA modification influences thousands of genes: Revolutionizes understanding of gene expression.
Novel RNA transport mechanism: Ribonucleoprotein granules exit the nucleus via a budding mechanism. Locked down, RNA editing yields odd fly behavior. New 'genetic bar code' technique establishes ability to derive DNA information from RNA. 3-D RNA modeling opens scientific doors. Strange cousins: Molecular alternatives to DNA, RNA offer new insight into life’s origins. Correcting human mitochondrial mutations. A double ring ceremony prepares telomerase RNA to wed its protein partner. Need for speed: Molecular ticket determines RNA’s destination and speed inside egg cell. Hotspots for biogenesis of small RNA molecules in plant cells discovered. Early evolution of life: Study of ribosome evolution challenges 'RNA World' hypothesis. Turning off small RNA: New tool designed for breaking the epigenetic code. RNA interference cancer treatment? Delivering RNA with tiny sponge-like spheres. Computer sleuthing helps unravel RNA's role in cellular function.
Cellular switches: From the RNA world to the 'modern' protein world. Cellular switches: From the RNA world to the 'modern' protein world. New RNA-based therapeutic strategies for controlling gene expression. New information for flu fight: Researchers study RNA interference to determine host genes used by influenza for virus replication. Scientists create novel RNA repair technology. Simpler times: Did an earlier genetic molecule predate DNA and RNA? A radar for ADAR: Altered gene tracks RNA editing in neurons. Built-in 'self-destruct timer' causes ultimate death of messenger RNA in cells. Computer assisted design (CAD) for RNA. Acquired traits can be inherited via small RNAs. Long non-coding RNA prevents the death of maturing red blood cells. Mechanisms cells use to remove bits of RNA from DNA strands.
Synthetic RNA lessens severity of fatal disease. Cancer drug cisplatin found to bind like glue in cellular RNA. New roles emerge for non-coding RNAs in directing embryonic development. New research links common RNA modification to obesity. New role for RNA interference during chromosomal replication discovered. Novel technique uses RNA interference to block inflammation. New technique gives precise picture of how regulatory RNA controls gene activity. A micro-RNA as a key regulator of learning and Alzheimer's disease.
Team finds stable RNA nano-scaffold within virus core. Fragile X-associated tremor/ataxia syndrome may be linked to dysregulated neuronal RNA transport, study suggests. Powerful fluorescence tool lights the way to new insights into RNA of living cells. Hitting moving RNA drug targets: New way to search for novel drugs. Non-coding RNA has role in inherited neurological disorder, and maybe other brain diseases too. Key function of enzyme involved in RNA processing described. Removal of a tiny RNA molecule can inhibit cancer growth, researchers discover. Noncoding RNA may promote Alzheimer's disease. New level of genetic diversity discovered in human RNA sequences. Work with RNA silencing and plant stem cells may lead to controlling fruit, seed and leaves.
RNA spurs melanoma development; Potential new diagnostic marker for skin cancer. RNA dynamics deconstructed. RNA nanoparticles constructed to safely deliver long-lasting therapy to cells. Micro-RNA blocks the effect of insulin in obesity. Micro-RNA's contribute to risk for panic disorder.