Are RNA fragments making gene tweaks in descendants? - life - 13 April 2014. A solution may be nigh to one of the biggest mysteries of biology – how the effects of a person's lifestyle can be passed on to future generations without any changes to the genetic code. This phenomenon, called epigenetic inheritance, has been implicated in a multitude of modern ills, enabling stresses experienced by one generation to be passed to the next, and resulting in conditions such as schizophrenia, bipolar disorder and obesity. But failure to identify the detailed mechanism by which this happens has left many geneticists doubtful that it happens at all. Now Isabelle Mansuy of the University of Zurich in Switzerland and her colleagues have identified a mechanism in mice that sidesteps the usual objections. Their work suggests that the process relies on tiny fragments of RNA in sperm that can pass "echoes" of environmental experience down to future generations. Daring but despairing Behaviourally, the stressed mice end up more daring yet more despairing than normal mice.
Are RNA fragments making gene tweaks in descendants? - life - 13 April 2014. A solution may be nigh to one of the biggest mysteries of biology – how the effects of a person's lifestyle can be passed on to future generations without any changes to the genetic code. This phenomenon, called epigenetic inheritance, has been implicated in a multitude of modern ills, enabling stresses experienced by one generation to be passed to the next, and resulting in conditions such as schizophrenia, bipolar disorder and obesity. But failure to identify the detailed mechanism by which this happens has left many geneticists doubtful that it happens at all. Now Isabelle Mansuy of the University of Zurich in Switzerland and her colleagues have identified a mechanism in mice that sidesteps the usual objections. Their work suggests that the process relies on tiny fragments of RNA in sperm that can pass "echoes" of environmental experience down to future generations.
Daring but despairing Behaviourally, the stressed mice end up more daring yet more despairing than normal mice. (YouTube) Earth's first life may have sprung up in ice - life - 01 November 2013. IF YOU thought life evolved in bubbling hot springs, think again. Pieces of RNA have been made that can copy RNA strands longer than themselves, supporting the idea that the first life was based on self-replicating RNA, not DNA. What's more, they work best in the cold, hinting that life began on ice. RNA is a jack-of-all trades. Like DNA it can store genetic material, but it can also catalyse chemical reactions. For this reason, many believe it was the basis of the first life. If this was the case then those early organisms must have had an enzyme created out of RNA to copy their RNA genomes. But no known RNA enzyme can copy a stretch of RNA as long as itself, without which RNA organisms couldn't have survived for long.
To find such an enzyme, Philipp Holliger of the MRC Laboratory of Molecular Biology in Cambridge, UK, has been creating libraries of RNA sequences and screening them for the ability to copy other RNA. Their latest creation goes a step further. More From New Scientist. Earth's first life may have sprung up in ice - life - 01 November 2013. IF YOU thought life evolved in bubbling hot springs, think again. Pieces of RNA have been made that can copy RNA strands longer than themselves, supporting the idea that the first life was based on self-replicating RNA, not DNA.
What's more, they work best in the cold, hinting that life began on ice. RNA is a jack-of-all trades. Like DNA it can store genetic material, but it can also catalyse chemical reactions. For this reason, many believe it was the basis of the first life. If this was the case then those early organisms must have had an enzyme created out of RNA to copy their RNA genomes.
To find such an enzyme, Philipp Holliger of the MRC Laboratory of Molecular Biology in Cambridge, UK, has been creating libraries of RNA sequences and screening them for the ability to copy other RNA. Their latest creation goes a step further. Crucially, the enzyme does not yet copy itself. The RNA enzyme's effectiveness at cold temperatures suggests ice was crucial to the first life. Martian soup may have been tasty to early life - space - 01 September 2013. Read full article Continue reading page |1|2 Martian minerals dissolved in groundwater are much more likely to yield a key building block for life – phosphate – than dissolved minerals on Earth. At least, that's the finding of a lab-based physical simulation designed to work out the habitability of ancient environments on the Red Planet. The news comes just a few days after a prominent chemist aired his theory that only on Mars were the right chemical elements – specifically boron, molybdenum and oxygen – present at the right time to produce RNA molecules.
RNA is widely thought to be the precursor to DNA and therefore to life as we know it. Both studies have brought renewed attention to the idea that life on Earth was seeded from space, a theory known as panspermia. However, they can't both be right. The latest work focuses on phosphate, a molecule made up of one phosphorus atom and four oxygen atoms. Mineral broth Low hurdle Wet vs. dry More From New Scientist More from the web Recommended by. New vaccine may give lifelong protection from flu - health - 25 November 2012.
Flu season has come early this year in parts of the northern hemisphere, and many people are scrambling to get their annual vaccination. That ritual may someday be history. In a first for any infectious disease, a vaccine against flu has been made out of messenger RNA (mRNA) – the genetic material that controls the production of proteins. Unlike its predecessors, the new vaccine may work for life, and it may be possible to manufacture it quickly enough to stop a pandemic. We become immune to a flu strain when our immune system learns to recognise key proteins, called HA and NA, on the surface of the flu virus. Flu constantly evolves, however, so those proteins change and your immunity to one year's strain does not extend to following year's. This time lag means that the World Health Organization has to predict months in advance which viruses are most likely to be circulating the following winter.
Freeze-dried vaccine Now there could be a solution. Safety advantage Two-pronged immunity. First life may have survived by cooperating - life - 17 October 2012. It began with cooperation. When life first arose, teams of small molecules got together to perform tasks none could manage alone or so the theory goes.
For the first time, networks like this have been built in the lab. The earliest life may have been a primordial soup of RNA molecules, but the first crude self-replicating molecules in this "RNA world" would have faced a big problem. They had to grow to store more information, but that made copying errors more likely. Get big enough and these errors become almost certain, destroying the molecule's information. In theory, the first replicators could have avoided this "error catastrophe" by splitting their information between several cooperating molecules.
Repair one for the team To see if this strategy would work, Niles Lehman of Portland State University in Oregon and colleagues created three RNA molecules that could repair each other – A did B, B did C, and C did A. Stick together Journal reference: Nature, DOI: 10.1038/nature11549 (YouTube) First life may have survived by cooperating - life - 17 October 2012. It began with cooperation. When life first arose, teams of small molecules got together to perform tasks none could manage alone or so the theory goes.
For the first time, networks like this have been built in the lab. The earliest life may have been a primordial soup of RNA molecules, but the first crude self-replicating molecules in this "RNA world" would have faced a big problem. They had to grow to store more information, but that made copying errors more likely. In theory, the first replicators could have avoided this "error catastrophe" by splitting their information between several cooperating molecules. Repair one for the team To see if this strategy would work, Niles Lehman of Portland State University in Oregon and colleagues created three RNA molecules that could repair each other – A did B, B did C, and C did A.
When the team put these broken molecules together in a test tube, the collective network worked well. Stick together Journal reference: Nature, DOI: 10.1038/nature11549. Protein discovery could lead to 'genomic debuggers' - health - 02 September 2012. THE trick could have come from a thrifty plumber: why replace a leaky pipe if you can simply patch it up? A single fault in DNA can travel a long way. It may be copied into RNA, which then produces the faulty proteins that underlie some genetic disorders. Now biologists have laid the groundwork for creating tools designed to bind to faulty RNA and fix protein production. The tools are themselves proteins. Ian Small at the University of Western Australia, Crawley, and his colleagues identified a special class of RNA-binding proteins 12 years ago.
"One vision of their activity is as genomic debuggers - they correct mutations at the RNA level," he says. Small's team has now worked out how their RNA-binding proteins, called PPR, latch on to RNA. The finding paves the way for building "designer PPR proteins" that target and fix specific genes, Small says. More From New Scientist Is full-fat milk best? First direct sighting of an extrasolar planet (New Scientist) More from the web Recommended by. Protein discovery could lead to 'genomic debuggers' - health - 02 September 2012. THE trick could have come from a thrifty plumber: why replace a leaky pipe if you can simply patch it up? A single fault in DNA can travel a long way. It may be copied into RNA, which then produces the faulty proteins that underlie some genetic disorders. Now biologists have laid the groundwork for creating tools designed to bind to faulty RNA and fix protein production.
The tools are themselves proteins. Ian Small at the University of Western Australia, Crawley, and his colleagues identified a special class of RNA-binding proteins 12 years ago. "One vision of their activity is as genomic debuggers - they correct mutations at the RNA level," he says. Small's team has now worked out how their RNA-binding proteins, called PPR, latch on to RNA. The finding paves the way for building "designer PPR proteins" that target and fix specific genes, Small says.
New Scientist Not just a website! More From New Scientist Space-time ripples hint at physics beyond the big bang (New Scientist) Recommended by. Is God's mercy to blame for high crime rates? - science-in-society - 22 June 2012. There's nothing like the fear of eternal damnation to encourage low crime rates. But does belief in heaven and a forgiving god encourage lawbreaking? A new study suggests it might – although establishing a clear link between the two remains a challenge. Azim Shariff at the University of Oregon in Eugene and his colleagues compared global data on people's beliefs in the afterlife with worldwide crime data collated by the United Nations Office on Drugs and Crime.
In total, Shariff's team looked at data covering the beliefs of 143,000 individuals across 67 countries and from a variety of religious backgrounds. In most of the countries assessed, people were more likely to report a belief in heaven than in hell. Using that information, the team could calculate the degree to which a country's rate of belief in heaven outstrips its rate of belief in hell. Licence to steal God helps those who… "When you take all of this research together, it does start to build a stronger case," says Shariff. 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. 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.
Before DNA, before RNA: Life in the hodge-podge world - life - 08 January 2012. Take note, DNA and RNA: it's not all about you. Life on Earth may have begun with a splash of TNA – a different kind of genetic material altogether. Because RNA can do many things at once, those studying the origins of life have long thought that it was the first genetic material. But the discovery that a chemical relative called TNA can perform one of RNA's defining functions calls this into question. Instead, the very first forms of life may have used a mix of genetic materials. Today, most life bar some viruses uses DNA to store information, and RNA to execute the instructions encoded by that DNA. A key piece of evidence for this "RNA world" hypothesis is that RNA is a jack of all trades. Now it seems TNA might have been just as capable, although it is not found in nature today.
It differs from RNA and DNA in its sugar backbone: TNA uses threose where RNA uses ribose and DNA deoxyribose. The team took a library of TNAs and evolved them in the presence of a protein. No TNA world. Before DNA, before RNA: Life in the hodge-podge world - life - 08 January 2012. Take note, DNA and RNA: it's not all about you. Life on Earth may have begun with a splash of TNA – a different kind of genetic material altogether. Because RNA can do many things at once, those studying the origins of life have long thought that it was the first genetic material. But the discovery that a chemical relative called TNA can perform one of RNA's defining functions calls this into question. Instead, the very first forms of life may have used a mix of genetic materials. Today, most life bar some viruses uses DNA to store information, and RNA to execute the instructions encoded by that DNA.
A key piece of evidence for this "RNA world" hypothesis is that RNA is a jack of all trades. Now it seems TNA might have been just as capable, although it is not found in nature today. It differs from RNA and DNA in its sugar backbone: TNA uses threose where RNA uses ribose and DNA deoxyribose. The team took a library of TNAs and evolved them in the presence of a protein. No TNA world. Forget antibiotics, try nanoparticles instead - health - 03 December 2011. Before DNA, before RNA: Life in the hodge-podge world - life - 08 January 2012. Self-tidying molecules could have kick-started life - life - 22 July 2011.