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Mice embryos grow a bigger brain with human DNA

Mice embryos grow a bigger brain with human DNA | Amazing Science | Scoop.it

The size of the human brain expanded dramatically during the course of evolution, imparting us with unique capabilities to use abstract language and do complex math. But how did the human brain get larger than that of our closest living relative, the chimpanzee, if almost all of our genes are the same?


Duke scientists have shown that it's possible to pick out key changes in the genetic code between chimpanzees and humans and then visualize their respective contributions to early brain development by using mouse embryos. The team found that humans are equipped with tiny differences in a particular regulator of gene activity, dubbed HARE5, that when introduced into a mouse embryo, led to a 12% bigger brain than in the embryos treated with the HARE5 sequence from chimpanzees.


The findings, appearing online Feb. 19, 2015, in Current Biology, may lend insight into not only what makes the human brain special but also why people get some diseases, such as autism and Alzheimer's disease, whereas chimpanzees don't.


"I think we've just scratched the surface, in terms of what we can gain from this sort of study," said Debra Silver, an assistant professor of molecular genetics and microbiology in the Duke University Medical School. "There are some other really compelling candidates that we found that may also lead us to a better understanding of the uniqueness of the human brain."


Every genome contains many thousands of short bits of DNA called 'enhancers,' whose role is to control the activity of genes. Some of these are unique to humans. Some are active in specific tissues. But none of the human-specific enhancers previously had been shown to influence brain anatomy directly.


In the new study, researchers mined databases of genomic data from humans and chimpanzees, to find enhancers expressed primarily in the brain tissue and early in development. They prioritized enhancers that differed markedly between the two species. The group's initial screen turned up 106 candidates, six of them near genes that are believed to be involved in brain development. The group named these 'human-accelerated regulatory enhancers,' HARE1 through HARE6.


The strongest candidate was HARE5 for its chromosomal location near a gene called Frizzled 8, which is part of a well-known molecular pathway implicated in brain development and disease. The group decided to focus on HARE5 and then showed that it was likely to be an enhancer for Frizzled8 because the two DNA sequences made physical contact in brain tissue.


The human HARE5 and the chimpanzee HARE5 sequences differ by only 16 letters in their genetic code. Yet, in mouse embryos the researchers found that the human enhancer was active earlier in development and more active in general than the chimpanzee enhancer.


"What's really exciting about this was that the activity differences were detected at a critical time in brain development: when neural progenitor cells are proliferating and expanding in number, just prior to producing neurons," Silver said.

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Human sex redefined: The idea of two sexes is simplistic. Biologists now think there is a wider spectrum than that

Human sex redefined: The idea of two sexes is simplistic. Biologists now think there is a wider spectrum than that | Amazing Science | Scoop.it

As a clinical geneticist, Paul James is accustomed to discussing some of the most delicate issues with his patients. But in early 2010, he found himself having a particularly awkward conversation about sex.


A 46-year-old pregnant woman had visited his clinic at the Royal Melbourne Hospital in Australia to hear the results of an amniocentesis test to screen her baby's chromosomes for abnormalities. The baby was fine — but follow-up tests had revealed something astonishing about the mother. Her body was built of cells from two individuals, probably from twin embryos that had merged in her own mother's womb. And there was more. One set of cells carried two X chromosomes, the complement that typically makes a person female; the other had an X and a Y. Halfway through her fifth decade and pregnant with her third child, the woman learned for the first time that a large part of her body was chromosomally male1. “That's kind of science-fiction material for someone who just came in for an amniocentesis,” says James.


Sex can be much more complicated than it at first seems. According to the simple scenario, the presence or absence of a Y chromosome is what counts: with it, you are male, and without it, you are female. But doctors have long known that some people straddle the boundary — their sex chromosomes say one thing, but their gonads (ovaries or testes) or sexual anatomy say another. Parents of children with these kinds of conditions — known as intersex conditions, or differences or disorders of sex development (DSDs) — often face difficult decisions about whether to bring up their child as a boy or a girl. Some researchers now say that as many as 1 person in 100 has some form of DSD2.


When genetics is taken into consideration, the boundary between the sexes becomes even blurrier. Scientists have identified many of the genes involved in the main forms of DSD, and have uncovered variations in these genes that have subtle effects on a person's anatomical or physiological sex. What's more, new technologies in DNA sequencing and cell biology are revealing that almost everyone is, to varying degrees, a patchwork of genetically distinct cells, some with a sex that might not match that of the rest of their body. Some studies even suggest that the sex of each cell drives its behaviour, through a complicated network of molecular interactions. “I think there's much greater diversity within male or female, and there is certainly an area of overlap where some people can't easily define themselves within the binary structure,” says John Achermann, who studies sex development and endocrinology at University College London's Institute of Child Health.


These discoveries do not sit well in a world in which sex is still defined in binary terms. Few legal systems allow for any ambiguity in biological sex, and a person's legal rights and social status can be heavily influenced by whether their birth certificate says male or female.


“The main problem with a strong dichotomy is that there are intermediate cases that push the limits and ask us to figure out exactly where the dividing line is between males and females,” says Arthur Arnold at the University of California, Los Angeles, who studies biological sex differences. “And that's often a very difficult problem, because sex can be defined a number of ways.”


That the two sexes are physically different is obvious, but at the start of life, it is not. Five weeks into development, a human embryo has the potential to form both male and female anatomy. Next to the developing kidneys, two bulges known as the gonadal ridges emerge alongside two pairs of ducts, one of which can form the uterus and Fallopian tubes, and the other the male internal genital plumbing: the epididymes, vas deferentia and seminal vesicles. At six weeks, the gonad switches on the developmental pathway to become an ovary or a testis. If a testis develops, it secretes testosterone, which supports the development of the male ducts. It also makes other hormones that force the presumptive uterus and Fallopian tubes to shrink away. If the gonad becomes an ovary, it makes oestrogen, and the lack of testosterone causes the male plumbing to wither. The sex hormones also dictate the development of the external genitalia, and they come into play once more at puberty, triggering the development of secondary sexual characteristics such as breasts or facial hair.

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Mothers can pass traits to their offspring through bacteria's DNA, mouse study shows

Mothers can pass traits to their offspring through bacteria's DNA, mouse study shows | Amazing Science | Scoop.it

Researchers at Washington University School of Medicine in St. Louis has shown that the DNA of bacteria that live in the body can pass a trait to offspring in a way similar to the parents' own DNA. According to the authors, the discovery means scientists need to consider a significant new factor -- the DNA of microbes passed from mother to child -- in their efforts to understand how genes influence illness and health. The study appears online Feb. 16 in Nature.


Bacteria are most familiar through their roles in harmful infections. But scientists have realized that such bacteria are only a tiny fraction of the bacterial communities that live in and on our bodies. Most bacteria are commensal, which means they do not cause harm and often confer benefits.


Commensal bacteria influence traits such as weight and behavior. But until now, researchers thought the bacteria that exerted these effects were acquired during a person's life. The study is the first to show that bacterial DNA can pass from parent to offspring in a manner that affects specific traits such as immunity and inflammation.


The researchers linked commensal bacteria in mice to the animals' susceptibility to a gut injury. Mice with certain inherited bacteria are susceptible to the injury, which is caused by exposure to a chemical. Female mice pass the bacteria to their offspring, making them vulnerable to the injury. Others carrying different bacteria are less susceptible.


In several fields of research, scientists have been confronted intermittently with the sudden, unexplained appearance of new or altered traits in mice. The traits often spread from one mouse habitat to the next, suggesting a spreading microbial infection is responsible. But the traits also consistently pass from mother to offspring, suggesting a genetic cause.


Thaddeus Stappenbeck, MD, PhD, a professor of pathology and immunology, and co-senior author Virgin, the Edward Mallinckrodt Professor of Pathology and head of the Department of Pathology and Immunology, encountered this problem in their studies of inflammatory bowel diseases, such as Crohn's disease and ulcerative colitis. They were surprised to find that roughly half their mice had low levels in the gut of IgA, an antibody linked to these disorders.


IgA helps defend the body against harmful invaders. It is commonly present in mucus made by the body in areas where the exterior world encounters the body's interior, such as the eyes, nose, throat and gut. When the scientists housed mice with low levels of the antibody with mice that had high levels of the antibody, all of the mice ended up with low antibody levels in a few weeks. When they bred the mice, the offspring whose mothers had low levels of the antibody also had low levels.


Eventually, the scientists learned that one of the culprits likely responsible for the spread of low antibody levels is a bacterium called Sutterella. This bacterium and others found in the low-IgA mice could explain both ways that decreased antibody levels were spreading: Mice that were housed together acquired low antibody levels through normal spread of the bacteria, and mouse mothers passed the same bacteria to their descendants.

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Plants survive much better through mass extinctions than animals

Plants survive much better through mass extinctions than animals | Amazing Science | Scoop.it

At least 5 mass extinction events have profoundly changed the history of life on Earth. But a new study led by researchers at the University of Gothenburg shows that plants have been very resilient to those events.


For over 400 million years, plants have played an essential role in almost all terrestrial environments and covered most of the world’s surface. During this long history, many smaller and a few major periods of extinction severely affected Earth’s ecosystems and its biodiversity. In the upcoming issue of the journal New Phytologist, the team reports their results based on more than 20,000 plant fossils with the aim to understand the effects of such dramatic events on plant diversity. Their findings show that mass extinction events had very different impacts among plant groups. Negative rates of diversification in plants (meaning that more species died out than new species were formed) were never sustained through long time periods. This indicates that, in general, plants have been particularly good at surviving and recovering through tough periods.


Most striking were the results for the Cretaceous-Paleogene mass extinction, caused by the impact of an asteroid off the Mexican coast some 66 million years ago. This event had a great impact on the configuration of terrestrial habitats and led to the extinction of all dinosaurs except birds, but surprisingly it had only limited effects on plant diversity.


Some important plant groups, such as the gymnosperms (including pines, spruce and firs) lost a great deal of their diversity through extinction. On the other hand, flowering plants (angiosperms) did not suffer from increased extinction, and shortly after the impact they underwent a new rapid increase in their diversity. These evolutionary dynamics contributed to make flowering plants dominate today’s global diversity above all other plant groups.

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Oil Eating Microbes Have Worldwide Underground Connections With Each Other

Oil Eating Microbes Have Worldwide Underground Connections With Each Other | Amazing Science | Scoop.it

Living deep underground ain't easy. In addition to hellish temperatures and pressures, there's not a lot to eat. Which is why oil reservoirs are the microbes’ cornucopia in this hidden realm. 

Microbes feast on many oil reservoirs, but it has been unclear how the micro-organisms got to those locales. One proposal has been that the microbes colonize a pool of dead algae corpses and then go along for the ride as the pool gets buried deeper and deeper and the algae slowly become oil. That’s the so-called "burial and isolation" hypothesis.

But under that set of rules each pool of oil should have its own unique microbes—and that's not the case, according to a recent study in the Journal of the International Society for Microbial Ecology. [Camilla L. Nesbø et al, Evidence for extensive gene flow and Thermotoga subpopulations in subsurface and marine environments]

Researchers surveyed the genetics of oil-eating microbes from around the world. They found that populations from Nevada to the North Sea matched up almost exactly. They also determined that microbes in the North Sea appear to have swapped genes with Japanese microbes despite the locations being more than 8,000 kilometers apart on the Earth’s surface. 

These findings suggest that the deep biosphere is actually filled with connections, and that microbes move from one oil reservoir to another, colonizing them almost as soon as they form in some cases. Or it could also be that marine microbes migrate down and then evolutionary selection pressure causes a convergence in the genetics that make it possible to survive under these extreme conditions. 

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Researchers Produce First Map of New York City Subway System Microbes

Researchers Produce First Map of New York City Subway System Microbes | Amazing Science | Scoop.it

The microbes that call the New York City subway system home are mostly harmless, but include samples of disease-causing bacteria that are resistant to drugs — and even DNA fragments associated with anthrax and Bubonic plague — according to a citywide microbiome map published today by Weill Cornell Medical College investigators.


The study, published in Cell Systems, demonstrates that it is possible and useful to develop a "pathogen map" — dubbed a "PathoMap" — of a city, with the heavily traveled subway a proxy for New York's population. It is a baseline assessment, and repeated sampling could be used for long-term, accurate disease surveillance, bioterrorism threat mitigation, and large scale health management for New York, says the study's senior investigator, Dr. Christopher E. Mason, an assistant professor in Weill Cornell's Department of Physiology and Biophysics and in the HRH Prince Alwaleed Bin Talal Bin Abdulaziz Al-Saud Institute for Computational Biomedicine (ICB).


The PathoMap findings are generally reassuring, indicating no need to avoid the subway system or use protective gloves, Dr. Mason says. The majority of the 637 known bacterial, viral, fungal and animal species he and his co-authors detected were non-pathogenic and represent normal bacteria present on human skin and human body. Culture experiments revealed that all subway sites tested possess live bacteria.


Strikingly, about half of the sequences of DNA they collected could not be identified — they did not match any organism known to the National Center for Biotechnology Information or the Centers for Disease Control and Prevention. These represent organisms that New Yorkers touch every day, but were uncharacterized and undiscovered until this study. The findings underscore the vast potential for scientific exploration that is still largely untapped and yet right under scientists' fingertips.


"Our data show evidence that most bacteria in these densely populated, highly trafficked transit areas are neutral to human health, and much of it is commonly found on the skin or in the gastrointestinal tract," Dr. Mason says. "These bacteria may even be helpful, since they can out-compete any dangerous bacteria."


But the researchers also say that 12 percent of the bacteria species they sampled showed some association with disease. For example, live, antibiotic-resistant bacteria were present in 27 percent of the samples they collected. And they detected two samples with DNA fragments of Bacillus anthracis (anthrax), and three samples with a plasmid associated with Yersinia pestis (Bubonic plague) — both at very low levels. Notably, the presence of these DNA fragments do not indicate that they are alive, and culture experiments showed no evidence of them being alive.


Yet these apparently virulent organisms are not linked to widespread sickness or disease, Dr. Mason says. "They are instead likely just the co-habitants of any shared urban infrastructure and city, but wider testing is needed to confirm this."


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Parasite creating deformed frogs with up to 10 legs in the Western U.S.

Parasite creating deformed frogs with up to 10 legs in the Western U.S. | Amazing Science | Scoop.it
A flatworm parasite called Ribeiroia ondatrae infects several species of frogs just as they're developing their limbs, causing an assortment of defects such as no legs or even multiple legs that jut out at weird angles from the frogs' bodies scientists say.


Watch a video of the deformed frogs.


The deformed frogs are often unable to move and either die or quickly get eaten by predators. Scientists already knew that the parasite was the culprit in the frog malformations, but the researchers wanted to find out whether known hot spots of Ribeiroia populations in four western states had changed since they were last surveyed in 1999. So in 2010 Pieter Johnson, an ecologist at the University of Colorado at Boulder, and colleagues gathered data on frogs and parasites in 48 wetlands in CaliforniaOregonWashington, and Montana.


The Ribeiroia parasite has a complex, multihost life cycle, which begins with the ramshorn snail, a creature common to many western U.S wetlands. The flatworm asexually clones itself inside the snail, stripping the mollusk of its gonads and converting it into a "parasite machine," Johnson said. Each night the snail releases hundreds of free-swimmingRibeiroia larvae, which seek out their next hosts—tadpoles—with "remarkable precision."


The parasite larvae penetrate the tadpoles' tissue and zero in on the developing limb buds, so that when a tadpole begins to metamorphose into a frog, its "primary system of locomotion doesn't work—it can't jump, can't swim," he said. "That's when the birds"—the parasite's final host—"zoom in and eat the young mutated frogs up like popcorn."


The parasite then reproduces sexually inside the birds, and when the birds defecate, their feces contain parasite eggs that eventually make their way back into the snails.


Though the Ribeiroia parasite occurs naturally in North America, human activities likely have something to do with its prevalence, Johnson noted. For instance, the snails feed on algae, and runoff from agriculture and industry into wetlands contains nutrients that act as fertilizer, boosting algae growth. With more snails in the wetlands, the parasites have more initial hosts to infect, Johnson noted.

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Dogs know that smile: Animals other than humans can discriminate between emotional expressions of other species

Dogs know that smile: Animals other than humans can discriminate between emotional expressions of other species | Amazing Science | Scoop.it

Dogs can tell the difference between happy and angry human faces, according to a new study in the Cell Press journal Current Biology on February 12. The discovery represents the first solid evidence that an animal other than humans can discriminate between emotional expressions in another species, the researchers say. "We think the dogs in our study could have solved the task only by applying their knowledge of emotional expressions in humans to the unfamiliar pictures we presented to them," says Corsin Müller of the University of Veterinary Medicine Vienna.


Previous attempts had been made to test whether dogs could discriminate between human emotional expressions, but none of them had been completely convincing. In the new study, the researchers trained dogs to discriminate between images of the same person making either a happy or an angry face. In every case, the dogs were shown only the upper or the lower half of the face. After training on 15 picture pairs, the dogs' discriminatory abilities were tested in four types of trials, including (1) the same half of the faces as in the training but of novel faces, (2) the other half of the faces used in training, (3) the other half of novel faces, and (4) the left half of the faces used in training.


The dogs were able to select the angry or happy face more often than would be expected by random chance in every case, the study found. The findings show that not only could the dogs learn to identify facial expressions, but they were also able to transfer what they learned in training to new cues.


"Our study demonstrates that dogs can distinguish angry and happy expressions in humans, they can tell that these two expressions have different meanings, and they can do this not only for people they know well, but even for faces they have never seen before," says Ludwig Huber, senior author and head of the group at the University of Veterinary Medicine Vienna's Messerli Research Institute.

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Evolution of complex bioluminescent traits may be predictable

Evolution of complex bioluminescent traits may be predictable | Amazing Science | Scoop.it

A longstanding question among scientists is whether evolution is predictable. A team of researchers from UC Santa Barbara may have found a preliminary answer. The genetic underpinnings of complex traits in cephalopods may in fact be predictable because they evolved in the same way in two distinct species of squid.


Last, year, UCSB professor Todd Oakley and then-Ph.D. student Sabrina Pankey profiled bioluminescent organs in two species of squid and found that while they evolved separately, they did so in a remarkably similar manner. Their findings are published today in the Proceedings of the National Academy of Science.


Oakley, professor and vice chair of UCSB’s Department of Ecology, Evolution and Marine Biology, and Pankey, now a postdoctoral scholar at the University of New Hampshire, leveraged advances in sequencing technology and cutting-edge genomic tools to test predictability in the evolution of biological light production.


They chose to work with the Hawaiian bobtail squid (Euprymna scolopes) and the swordtip squid (Uroteuthis edulis), a Japanese species used for sushi. These distantly related species are two of five genera known to have bioluminescent organs called photophores. The photophores contain symbiotic, light-emitting bacteria, and the squid are capable of controlling the aperture of their organ to modulate how much light is produced.


The scientists wanted to know how similar the two species’ photophores are in terms of their genetic makeup. To find the answer, they sequenced all of the genes expressed in these light organs, something that could not be done using older sequencing technology.


“They are much more similar than we expected in terms of their genetic makeup,” Oakley said. “Usually when two complicated organs evolve separately we would expect them to take very different evolutionary paths to arrive where they are today. The unexpectedly similar genetic makeup demonstrates that these two squid species took very similar paths to evolve these traits.”


More specifically, the researchers demonstrated that bioluminescent organs originated repeatedly during squid evolution and then showed that the global gene expression profiles (transcriptomes) underlying those organs are strikingly — even predictably — similar. To confirm their hypothesis and findings, Oakley and Pankey enlisted the assistance of statisticians from the University of Washington and UCLA, who developed new statistical methods to test the idea of convergent (separately evolved) origins.


“I did find some individual genes that were counter to the main pattern, which means we can no longer study just one gene anymore in order to test these questions about the genetic basis of convergence,” said Pankey. “We’re at the point now where we need to — and can  — study all of them.”


Some previous experiments have indicated that these squid use their bioluminescent capabilities for camouflage, as counterintuitive as that may seem. “If you imagine lying on your back in the deep ocean and looking up, almost all the light comes from straight above,” Oakley explained. “There’s no structure like walls or trees to reflect the light, so if there’s something above you, it’s going to cast a shadow. The squid can produce light that then matches the light from behind them so it blocks their shadow to a viewer below, which is a type of camouflage.”

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Even cockroaches have individual personalities that impact group dynamics

Even cockroaches have individual personalities that impact group dynamics | Amazing Science | Scoop.it

A team of researchers working at Université libre de Bruxelles has found that not only do cockroaches have unique individual personalities, but their differences can also have an impact on group dynamics. In their paper published in Proceedings of the Royal Society B, the group describes the experiments they conducted as part of their study and why what they learned might help explain why roaches are so good at surviving in different types of environments.


Prior research has shown that humans are not the only ones with unique personalities, other animals such as dogs and cats and many other mammals have been found to behave differently depending on their personality—also, scientists have found that a host of invertebrates also have unique personalities. In this new study the researchers sought to discover if the same was true for cockroaches.


To find out, the group assembled 19 groups of cockroaches with 16 individual same-age males in each. All had tiny transmitters attached so that their movements could be precisely tracked. Each group was released into a plastic arena (three times a week) from which they could not escape—which was initially completely dark. Just above the arena, the team placed several disks that would cast shadows down below when the lights were turned on. This allowed the researchers to track the roaches as they sought to hide in the shadows, or not, both individually, and when they were members of a group.


In analyzing the behavior of the cockroaches, the researchers found that there were clear differences in personality between individuals—when left alone, some would scurry to hide as soon as the light was turned on, while others dawdled or ignored the light altogether. They also found that some took a lot longer to work up the nerve to venture out after the light remained on for a long period of time. The researchers also found that the individual personalities tended to result in a group personality that was evidenced by how long it took a group as a whole to hide in the shade after the lights came on or how long it took to disperse. Notably, they also found that the behavior of the individual roaches was different depending on if they were alone or in a group—running to hide, for example when with a group when they would not do so when alone.

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Sandeep Gautam's curator insight, February 5, 12:36 PM

Personality is evolutionarily deep!

Sean lim's curator insight, February 8, 7:44 AM

Cockroaches will one day rule the earth(as shown in fairlyoddparents) due to their supreme leader rising.

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Sea Slug has Taken Genes from the Algae it Eats, Allowing it to Photosynthesize Like a Plant

Sea Slug has Taken Genes from the Algae it Eats, Allowing it to Photosynthesize Like a Plant | Amazing Science | Scoop.it

How a brilliant-green sea slug manages to live for months at a time “feeding” on sunlight, like a plant, is clarified in a recent study published in The Biological BulletinThe authors present the first direct evidence that the emerald green sea slug’s chromosomes have some genes that come from the algae it eats. These genes help sustain photosynthetic processes inside the slug that provide it with all the food it needs. Importantly, this is one of the only known examples of functional gene transfer from one multicellular species to another, which is the goal of gene therapy to correct genetically based diseases in humans.


“Is a sea slug a good [biological model] for a human therapy? Probably not. But figuring out the mechanism of this naturally occurring gene transfer could be extremely instructive for future medical applications,” says study co-author Sidney K. Pierce, an emeritus professor at University of South Florida and at University of Maryland, College Park.


The team used an advanced imaging technique to confirm that a gene from the alga V. litorea is present on the E. chlorotica slug’s chromosome. This gene makes an enzyme that is critical to the function of photosynthetic “machines” called chloroplasts, which are typically found in plants and algae.


It has been known since the 1970s that E. chloritica “steals” chloroplasts from V. litorea (called “kleptoplasty”) and embeds them into its own digestive cells. Once inside the slug cells, the chloroplasts continue to photosynthesize for up to nine months—much longer than they would perform in the alga. The photosynthesis process produces carbohydrates and lipids, which nourish the slug.


How the slug manages to maintain these photosynthesizing organelles for so long has been the topic of intensive study and a good deal of controversy. “This paper confirms that one of several algal genes needed to repair damage to chloroplasts, and keep them functioning, is present on the slug chromosome,” Pierce says. “The gene is incorporated into the slug chromosome and transmitted to the next generation of slugs.” While the next generation must take up chloroplasts anew from algae, the genes to maintain the chloroplasts are already present in the slug genome, Pierce says.


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Richard Spencer's curator insight, February 5, 6:00 AM

The  wonders  of  evolution  

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Female sticklebacks prime their offspring to cope with climate change

Female sticklebacks prime their offspring to cope with climate change | Amazing Science | Scoop.it

Researchers at the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) have shown that three-spined sticklebacks in the North Sea pass on information concerning their living environment to their offspring, without genetic changes. This could play an important role in the species´ ability to adapt to the effects of climate change, as AWI experts report in a recently published study in the journal Functional Ecology. Interestingly, this information transfer appears to be primarily the mother's responsibility; in this study, the father's temperature experiences were much less significant.

Climate change and the accompanying warming of the oceans are of key interest to researchers around the globe. Above all, they want to know: What will happen to marine life forms if the predicted changes become a reality? Will the various species be able to adapt to the rising water temperatures? In an effort to answer these questions, Dr Lisa Shama and Dr Mathias Wegner from the AWI-Sylt examined three-spined sticklebacks (Gasterosteus aculeatus) taken from the Wadden Sea off the coast of Sylt.


Over the course of several months of laboratory testing, they investigated whether the environmental experiences gathered by the parent fish alone can influence growth rates of their offspring. "Our focus wasn't on genetic heredity, but instead on gene-independent information transfer. Because if these effects can be confirmed, they could play an important part in coping with the effects of rapid climate changes," says biologist Mathias Wegner.


The conclusion: The information is stored in the mitochondria


Recapping the study's findings, Mathias Wegner states, "Female sticklebacks pass on optimised mitochondria, which have adapted to the environmental conditions the mothers experienced, to their offspring. As a result the young fish receive information on their mothers' environment and living conditions without any genetic changes. In this species, then, maternal effects play a decisive role in terms of the potential to adapt to changes in their habitat."

This mechanism works particularly well in less favourable environments - which for sticklebacks means in warmer waters. According to Lisa Shama, "We can then conclude that the information-sharing mechanism - passing on the optimally acclimated mitochondria - represents a selective advantage and is likely the result of evolution."

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Scientists discover organism that hasn't evolved in more than 2 billion years

Scientists discover organism that hasn't evolved in more than 2 billion years | Amazing Science | Scoop.it

An international team of scientists has discovered the greatest absence of evolution ever reported—a type of deep-sea microorganism that appears not to have evolved over more than 2 billion years. But the researchers say that the organisms' lack of evolution actually supports Charles Darwin's theory of evolution.

The scientists examined sulfur bacteria, microorganisms that are too small to see with the unaided eye, that are 1.8 billion years old and were preserved in rocks from Western Australia's coastal waters. Using cutting-edge technology, they found that the bacteria look the same as bacteria of the same region from 2.3 billion years ago—and that both sets of ancient bacteria are indistinguishable from modern sulfur bacteria found in mud off of the coast of Chile.


"It seems astounding that life has not evolved for more than 2 billion years—nearly half the history of the Earth," said J. William Schopf, a UCLA professor of earth, planetary and space sciences in the UCLA College who was the study's lead author.


"The rule of biology is not to evolve unless the physical or biological environment changes, which is consistent with Darwin," said Schopf, who also is director of UCLA's Center for the Study of Evolution and the Origin of Life. The environment in which these microorganisms live has remained essentially unchanged for 3 billion years, he said. "These microorganisms are well-adapted to their simple, very stable physical and biological environment," he said.


"If they were in an environment that did not change but they nevertheless evolved, that would have shown that our understanding of Darwinian evolution was seriously flawed." Schopf said the findings therefore provide further scientific proof for Darwin's work. "It fits perfectly with his ideas," he said.

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Pamela Hills's curator insight, February 22, 8:35 AM

It is amazing at what is being found that has not been seen fro thousands of years.

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Lunar moths shed light on how to fool sonar from bats

Lunar moths shed light on how to fool sonar from bats | Amazing Science | Scoop.it

It’s hard to hide from a bat: The camouflage and mimicry techniques that animals use to avoid becoming a meal aren’t much use against a predator using echolocation. But a new study shows that moths can outsmart sonar with a flick of their long tails.


The study appearing in the Proceedings of the National Academy of Sciences shows luna moths spin their trailing hindtails as they fly, confusing the sonar cries bats use to detect prey and other objects.


The collaborative work between University of Florida and Boise State University researchers is a first step in determining why bats are lured into striking a false target. The findings could have implications on sonar development for the military, said Akito Kawahara, assistant curator of Lepidoptera at the Florida Museum of Natural History on the UF campus, who was UF’s research leader on the project.

“This finding expands our knowledge of anti-predator deflection strategies and the extent of a long-standing evolutionary arms race between bats and moths,” Kawahara said.


The study is the first to show that insects use this type of trickery to thwart bats. Other animals also might use acoustic deflection strategies, said lead author Jesse Barber, a biologist at Boise State University. Using high-speed infrared cameras and ultrasonic microphones, the researchers watched brown bats preying on moths. Luna moths with tails were 47 percent more likely to survive an attack than moths without tails. Bats targeted the tail during 55 percent of the interactions, suggesting the moths may lure bats to the tails to make an attack more survivable.


While more than half of the 140,000 species of nocturnal moths have sonar-detecting ears that provide a similar level of protection, more than 65,000 species lack this defense, Kawahara said. “When you pit them against bats, bats can’t find the moths. They go to the tail instead of the head,” Kawahara said. “When you look at Lepidoptera collections, you see moths with really short tails and some with extremely long tails. This also is an example of the important role biological collections serve as repositories of patterns and processes of biodiversity.”

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Complex nerve-cell signaling traced back to common ancestor of humans and sea anemones

Complex nerve-cell signaling traced back to common ancestor of humans and sea anemones | Amazing Science | Scoop.it

New research shows that a burst of evolutionary innovation in the genes responsible for electrical communication among nerve cells in our brains occurred over 600 million years ago in a common ancestor of humans and the sea anemone. The research, led by Timothy Jegla, an assistant professor of biology at Penn State University, shows that many of these genes, which when mutated in humans can lead to neurological disease, first evolved in the common ancestor of people and a group of animals called cnidarians, which includes jellyfish, coral, and sea anemones.


"Our research group has been discovering evidence for a long time that most major signaling systems in our neurons are ancient, but we never really knew when they first appeared," Jegla said. "We had always assumed that we would be able to trace most of these signaling systems to the earliest nervous systems, but in this paper we show that this is not the case. It looks like the majority of these signaling systems first appear in the common ancestor that humans share with jellyfish and sea anemones."

Electrical impulses in nerve cells are generated by charged molecules known as ions moving into and out of the cell through highly specialized ion-channel proteins that form openings in the cell membrane. The new research focuses on the functional evolution of the genes that encode the proteins for potassium channels -- ion channels that allow potassium to flow out of nerve cells, stopping the cell's electrical impulses. "The channels are critical for determining how a nerve cell fires electrical signals," said Jegla. "It appears that animals such as sea anemones and jellyfish are using the same channels that shape electrical signals in our brains in essentially the same way."


"Humans and sea anemones went their separate ways evolutionarily speaking roughly 600 million years ago," said Jegla, "so we know that the mechanisms we use to generate impulses in our neurons must be at least that old."


Recent genome sequences from comb jellies, which also have nervous systems, show that they are a more ancient group of animals than sea anemones and might even be the oldest type of animals that are still living today. "When we looked at comb jellies, we found that the potassium channels looked very different -- most of the channel types found in humans were missing," said Jegla. "We could trace only one kind of the human potassium channels that we looked at all the way back to comb jellies, but we find almost all of them in sea anemones."

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Untapped Events's curator insight, February 19, 10:38 AM

 Investigação demonstra que os mecanismos que os nossos neurónios usam para gerar impulsos terá cerca de 600 milhões de anos.


Research shows that the mechanisms we use to generate impulses in our neurons must be at least 600 million years old.


‪#‎UntappedEvents‬ ‪#‎News‬ ‪#‎Science‬ ‪

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Bacteria jump between species more easily than previously thought

Bacteria jump between species more easily than previously thought | Amazing Science | Scoop.it

A new study suggests that bacteria may be able to jump between host species far easier than was previously thought. Researchers discovered that a single genetic mutation in a strain of bacteria infectious to humans enables it jump species to also become infectious to rabbits. The discovery has major implications for how we assess the risk of bacterial diseases that can pass between humans and animals. It is well known that relatively few mutations are required to support the transmission of viruses -- such as influenza -- from one species to another. Until now it was thought that the process was likely to be far more complicated for bacteria.


Scientists at the universities of CEU Cardenal Herrera (Spain) and Glasgow and Edinburgh (UK) studied a strain of bacteria called Staphylococcus aureus ST121, which is responsible for widespread epidemics of disease in the global rabbit farming industry. The team looked at the genetic make-up of ST121 to work out where the strain originated and the changes that occurred that enabled it to infect rabbits. They found that ST121 most likely evolved through a host jump from humans to rabbits around 40 years ago with a genetic mutation at a single site in the bacterial DNA code the cause for this.


The discovery transforms our understanding of the minimal genetic changes that are required for bacteria to infect different species. ST121 is found in the respiratory tract and on the skin of some people. While it is usually harmless, the bacteria can cause a variety of conditions from minor skin infections to meningitis and sepsis. In rabbits, the bacteria can cause serious skin infections.

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Limpet teeth consists of the strongest biological material ever tested

Limpet teeth consists of the strongest biological material ever tested | Amazing Science | Scoop.it

Limpets use a tongue bristling with tiny teeth to scrape food from rocks and also to carve out scars, which they nestle in when the tide goes out. The teeth are made of a mineral-protein composite, which the researchers tested in tiny fragments in the laboratory. They found it was stronger than spider silk, as well as all but the very strongest of man-made materials. The findings, published in the Royal Society's journal Interface, suggest that the secret to the material's strength is the thinness of its tightly-packed mineral fibers - a discovery that could help improve the man-made composites used to build aircraft, cars and boats, as well as dental fillings.


"Biology is a great source of inspiration as an engineer," said the study's lead author Dr Asa Barber, from the University of Portsmouth. "These teeth are made up of very small fibers, put together in a particular way - and we should be thinking about making our own structures following the same design principles." Those fibers, consisting of an iron-based mineral called goethite, are laced through a protein base in much the same way as carbon fibers can be used to strengthen plastic. The teeth themselves are less than a millimeter long, but Dr Barber and his colleagues ground ten of them into a tiny dog-bone shape in order to precisely measure the composite's tensile strength: the amount of force it can withstand before breaking.


The middle part of these samples was more than 100 times thinner than a human hair. With either end glued to specialized levers inside a device called an atomic force microscope, the engineers applied a pulling force to each of these milled tooth samples, until they snapped. The strength they calculated for the tooth material was, on average, about 5 GPa - some five times greater than most spider silk.


This sets a new record for biology, Dr Barber said, even when his team considered the most unusual spiders. People are always trying to find the next strongest thing, but spider silk has been the winner for quite a few years now," he explains. "So we were quite happy that the limpet teeth exceeded that.


"One of my colleagues on the paper, from Italy, found some exotic spider silk that was about 4.5 GPa, and we measured about 5 GPa."

This measurement is about the same as the pressure needed to turn carbon into diamond beneath the earth's crust. Alternatively, as Dr Barber explained, it can be compared to a single string of spaghetti holding up 3,000 half-kilogram bags of sugar. In terms of man-made materials, the limpet tooth is stronger than Kevlar fibers and almost as good as the best high-performance carbon fiber materials.

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Why are 10% of the world population left-handed? What are the advantages / disadvantages?

Why are 10% of the world population left-handed? What are the advantages / disadvantages? | Amazing Science | Scoop.it

Today, about one-tenth of the world’s population are southpaws. Why are such a small proportion of people left-handed -- and why does the trait exist in the first place? Daniel M. Abrams investigates how the uneven ratio of lefties and righties gives insight into a balance between competitive and cooperative pressures on human evolution.

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Animal Intelligence: Crows Understand Analogies

Animal Intelligence: Crows Understand Analogies | Amazing Science | Scoop.it

A recent research collaboration between Moscow State University and here at the University of Iowa has discovered that crows exhibit strong behavioral signs of analogical reasoning—the ability to solve puzzles like “bird is to air as fish is to what?” Analogical reasoning is considered to be the pinnacle of cognition and it only develops in humans between the ages of three and four.


Devising a task to study analogical thinking in animals is the next step. Here, the gist of analogycan be captured by arranging a matching task in which the relevant logical arguments are presented in the form of visual stimuli. Using letters of the alphabet for explanatory purposes, choosing test pair BB would be correct if the sample pair were AA, whereas choosing test pair EF would be correct if the sample pair were CD. Stated logically, A:A as B:B (same = same) and C:D as E:F (different = different). Critically, no items in the correct test pair physically match any of the items in the sample pair; so, only the analogical relation of sameness can be used to solve the task. Early research suggested that only humans and apes can learn this analogy task; however, a more recent project indicated that baboons too can learn to select the pair of items that depicts the analogous same or different relationship as the sample pair.


Now, we have found that crows too can exhibit analogical thinking. Ed Wasserman, one of the authors of this article, and his colleagues in Moscow, Anna Smirnova, Zoya Zorina, and Tanya Obozova, first trained hooded crows on several tasks in which they had to match items that were the same as one another. The crows were presented with a tray containing three cups. The middle cup was covered by a card picturing a color, a shape, or a number of items. The other two side cups were also covered by cards—one the same as and one different from the middle card. The cup under the matching card contained food, but the cup under the nonmatching card was empty. Crows quickly learned to choose the matching card and to do so more quickly from one task to the next.


Then, the critical test was given. Each card now pictured a pair of items. The middle card would display pairs AA or CD, and the two side cards would display pair BB and pair EF. The relation between one pair of items must be appreciated and then applied to a new pair of items to generate the correct answer: the BB card in the case of AA or the EF card in the case of CD. For instance, if the middle card displayed a circle and a cross, then the correct choice would be the side card containing a square and a triangle rather than the side card containing two squares. 


Not only could the crows correctly perform this task, but they did so spontaneously, from the very first presentations, without ever being trained to do so.

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Curious monkeys share our thirst for knowledge, even if there are no immediate benefits

Curious monkeys share our thirst for knowledge, even if there are no immediate benefits | Amazing Science | Scoop.it

Monkeys are notoriously curious, and new research has quantified just how eager they are to gain new information, even if there are not immediate benefits. The findings offer insights into how a certain part of the brain shared by monkeys and humans plays a role in decision making, and perhaps even in some disorders and addictions in humans.


https://www.youtube.com/watch?v=kKoNMYE9Bgs

The study, by researchers at the University of Rochester and Columbia University, shows that rhesus macaques have such robust curiosity that they are willing to give up a surprisingly large portion of a potential prize in order to quickly find out if they selected the winning option at a game of chance.

“It’s like buying a lottery ticket that you can scratch off and find out if you win immediately, or you can buy one that has a drawing after the evening news,” explained Benjamin Hayden, co-senior author of the study and professor in brain and cognitive sciences at the University of Rochester. “Regardless, you won’t get the money any more quickly, or in the case of the monkeys, they won’t get the squirt of water any sooner. They will just find out if they selected the winning option.”

In the study published in Neuron, monkeys were presented with a video gambling task in which they consistently chose to learn in advance if they picked the winning option. The monkeys did not receive their prize any sooner, which was a measure of juice or water; they were simply informed immediately if they selected a winner.

“When it’s simply a choice between getting the information earlier or not, the monkeys show a pretty strong preference for getting it earlier. But what we really wanted to do is quantify this preference,” said first author and lead researcher Tommy Blanchard, a Ph.D. candidate in Hayden's lab.

In the video gambling experiments, graduated colored columns illustrated the amount of water that could be won. The monkeys were more curious about the gambles when the stakes—or columns—were higher. 

The researchers found the monkeys not only consistently selected the gamble that informed them if they picked a winner right away, but they were also willing to select that option when the winnings were up to 25 percent less than the gamble that required them to wait for the results. “One way to think about this is that this is the amount of water the monkeys were willing to pay for the information about if they made the correct choice,” explained Blanchard.

“That 25 percent was really surprising to us—that’s pretty big,” Hayden said. “These monkeys really, really want that information, and they do these gambling tasks repeatedly and never get bored of them—it's intrinsically motivated.”

According to the researchers, their study helps to build a broader understanding for how curiosity—information seeking—is processed and rewarded in the brain. 

Like monkeys, when curious we evaluate what we’d be willing to pay—or give up—to satisfy our curiosity, Hayden said. And in the case of gambling, there is also the potential of a prize to factor in. So when we make a choice, it depends on the sum of those two things: the gamble (the money you might win), and the value of finding out. And those two things need to be combined in order to make decisions about that gamble. 

Earlier work suggests that these components are combined in the brain’s dopamine system. This study looks at that one step earlier in the process, in a region of the brain called the Orbitofrontal cortex, or OFC.

“I think of the OFC as the workshop of economic value, where, in this case, you have the value of the gamble and the value of the information—the raw materials—but they haven’t yet been combined,” said Hayden. “This study seems to have revealed that the mixing of the raw materials happens somewhere between the OFC and the dopamine system. We now have two points in the circuit.” 

“One of the reasons this research is important,” Hayden said, “is because this basic desire for information turns out to be something that’s really corrupted in people with anxiety, depression, obsessive-compulsive disorder, and addiction, for example.” 

“We think that by understanding these basic circuits in monkeys we may gain insights that 10 to15 years down the road may lead to new treatments for these psychiatric diseases,” Hayden concluded.

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Biological Warfare: Parasitic Wasp Uses A Virus To Control Its Host

Biological Warfare: Parasitic Wasp Uses A Virus To Control Its Host | Amazing Science | Scoop.it

Viral venom? A parasitoid wasp, Dinocampus coccinellae, is able to manipulate its host, the ladybug Coleomegilla maculata — it uses a never-before seen RNA virus.


Parasitoid wasps are some of the most fascinating parasites on Earth. As adults, they are free-living little wasps that go about their day much like other Hymenopterans. But when it comes time to lay their eggs, they do not make nests of paper or mud; instead, they lay their eggs inside another creature. The larvae hatch in their host, and proceed to eat the host alive from the inside before erupting from the body, Aliens-style. Not surprisingly, most of the host species would not be particularly good sports about such invasive use of their organs, except that the wasps somehow take control of their hosts’ brains. Some species make the host stay calm while they’re led to their doom, while others turn their hosts into bodyguards, which will viciously defend the pupating wasp or wasps that literally just ate their way out of the animal’s body.


One such bodyguard relationship is found between the wasp Dinocampus coccinellae and its hosts, ladybugs (also called lady birds or lady beetles) like Coleomegilla maculata. The wasp uses its stinger/ovipositer (egg-laying structure) to lay its eggs inside the ladybug. The larvae develop inside the beetle, and after about 20 days, a single larva emerges, ready to pupate and transition into an adult wasp. It spins its cocoon between the ladybug’s legs and starts the transformation. Here’s where things get weird: rather than attacking the parasite that just stole from its body or leaving the pupating wasp to fend for itself, the ladybug stays with the cocoon, protecting it until the wasp hatches. Then, the ladybug returns to normal, and often can even go on to live a its regular beetle-y life, including feeding and reproducing like ludybugs do. Until now, scientists didn’t know how the larva managed to control its host so long after leaving its body. But new findings suggest that a symbiotic RNA virus works with the wasp to take over the ladybugs’ nervous system.


French and Canadian scientists first discovered the presence of a previously-unknown RNA virus, which they named D. coccinellae Paralysis Virus or DcPV for short, in the brains of parasitized ladybugs. But to tie the virus to the parasitic wasp, they had to show that the virus is present in the parasite’s ovaries, that it is transferred into the host when the eggs are laid, and that the virus is found in the neural tissue while the host’s behavior is modified. Using a multifaceted approach combining RNA sequencing, quantitative PCR, and transmission electron microscopy, they were able to show that the virus is the main player when it comes to the bodyguard behavior of the parasitized bugs.


The bodyguarding behavior is essentially a neurological disorder: the beetle is overcome with partial paralysis and tremors. Either it is partially paralyzed and simply lashes out in defense at anything that comes near, or it’s neurons are set to trigger when they normally wouldn’t, leading to thrashing behavior that is perceived as defensive. Either way, the team characterized the neural tissue in parasitized ladybugs and found that infection with DcPV caused swelling to axons and other trauma, and that infection with the virus — not wasp-derived venom compounds — is responsible for the bodyguarding behavior. “Our results suggest that changes in ladybeetle behaviour most likely result from DcPV replication in the cerebral ganglia rather than by a direct manipulation by the parasitic wasp” the authors explain in their conclusions. Their findings suggest that “DcPV is employed as a biological weapon by D. coccinellae to manipulate the behaviour of C. maculata.”

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Pictured together for the first time: A chemokine and its receptor (CXCR4)

Pictured together for the first time: A chemokine and its receptor (CXCR4) | Amazing Science | Scoop.it

The first crystal structure of the cellular receptor CXCR4 bound to an immune signaling protein called a chemokine has been reported by researchers. The structure answers longstanding questions about a molecular interaction that plays an important role in human development, immune responses, cancer metastasis and HIV infections.


"This new information could ultimately aid the development of better small molecular inhibitors of CXCR4-chemokine interactions -- inhibitors that have the potential to block cancer metastasis or viral infections," said Tracy M. Handel, PhD, professor of pharmacology at UC San Diego and senior author of the study.


CXCR4 is a receptor that sits on the outer surface of cells, sticking out like an antenna. When it receives a message, in the form of signaling molecules called chemokines, the receptor binds the chemokines and transmits the message to the inside of the cell. This signal relay helps cells migrate normally during development and inflammation. But CXCR4 signaling can also play a role in abnormal cell migration, such as when cancer cells metastasize. CXCR4 is infamous for another reason: HIV uses it to bind and infect human immune cells.


Despite its far-reaching consequences, researchers have long lacked data to show how exactly the CXCR4-chemokine interaction occurs, or even how many CXCR4 receptors a single chemokine molecule might simultaneously engage. This is because membrane receptors like CXCR4 are exceptionally challenging structural targets. The difficulty dramatically increases when studying such receptors in complexes with the proteins they bind.


To overcome these experimental challenges, Handel's team used a novel approach. They combined computational modeling and a technique known as disulfide trapping to stabilize the complex. Once stabilized, the researchers were able to use X-ray crystallography to determine the CXCR4-chemokine complex's 3D atomic structure.


This is the first time that a receptor like CXCR4 has been crystallized with a protein binding partner and the results revealed several new insights. First, the new crystal structure shows that one chemokine binds to just one receptor. Additionally, the structure reveals that the contacts between the receptor and its binding partner are more extensive than previously thought -- it is one very large contiguous surface of interaction rather than two separate binding sites.


"With more than 800 members, seven-transmembrane receptors like CXCR4 are the largest protein family in the human genome," added Raymond Stevens, PhD, provost professor and director of the Bridge Institute at the University of Southern California and co-corresponding author. "Each new structure opens up so many doors to understanding different aspects of human biology, and this time it is about chemokine signaling."

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GLG Pharma's curator insight, February 9, 8:05 AM

Great Achievement! And it only gets harder, designing drugs to fit the receptor!

Ronan Delisle's curator insight, February 18, 4:04 AM

ajouter votre aperçu ...

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Researchers discover RNA viral "Enigma machine"

Researchers discover RNA viral "Enigma machine" | Amazing Science | Scoop.it

Researchers have cracked a code that governs infections by a major group of viruses including the common cold and polio. Until now, scientists had not noticed the code, which had been hidden in plain sight in the sequence of the ribonucleic acid (RNA) that makes up this type of viral genome. But a paper published in the Proceedings of the National Academy of Sciences (PNAS) Early Edition by a group from the University of Leeds and University of York unlocks its meaning and demonstrates that jamming the code can disrupt virus assembly. Stopping a virus assembling can stop it functioning and therefore prevent disease.


Single-stranded RNA viruses are the simplest type of virus and were probably one of the earliest to evolve. However, they are still among the most potent and damaging of infectious pathogens. Rhinovirus (which causes the common cold) accounts for more infections every year than all other infectious agents put together (about 1 billion cases), while emergent infections such as chikungunya and tick-borne encephalitis are from the same ancient family. Other single-stranded RNA viruses include the hepatitis C virus, HIV and the winter vomiting bug norovirus.


This breakthrough was the result of three stages of research:

  • In 2012, researchers at the University of Leeds published the first observations at a single-molecule level of how the core of a single-stranded RNA virus packs itself into its outer shell—a remarkable process because the core must first be correctly folded to fit into the protective viral protein coat. The viruses solve this fiendish problem in milliseconds. The next challenge for researchers was to find out how the viruses did this.
  • University of York mathematicians Dr Eric Dykeman and Professor Reidun Twarock, working with the Leeds group, then devised mathematical algorithms to crack the code governing the process and built computer-based models of the coding system.
  • In this latest study, the two groups have unlocked the code. The group used single-molecule fluorescence spectroscopy to watch the codes being used by the satellite tobacco necrosis virus, a single stranded RNA plant virus.


Dr Roman Tuma, Reader in Biophysics at the University of Leeds, said: “We have understood for decades that the RNA carries the genetic messages that create viral proteins, but we didn’t know that, hidden within the stream of letters we use to denote the genetic information, is a second code governing virus assembly. It is like finding a secret message within an ordinary news report and then being able to crack the whole coding system behind it.


“This paper goes further: it also demonstrates that we could design molecules to interfere with the code, making it uninterpretable and effectively stopping the virus in its tracks.”


Reference: N. Patel et al. ‘Revealing the density of encoded functions in a viral RNA,’ PNAS (2014) is available to download (www.pnas.org/cgi/doi/10.1073/pnas.1420812112; DOI 10.1073/ pnas.1420812112).

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Venus Flytraps Risk Extinction in the Wild at the Hands of Poachers

Venus Flytraps Risk Extinction in the Wild at the Hands of Poachers | Amazing Science | Scoop.it

Earlier this month four men were arrested for poaching on the Holly Shelter Game Land preserve in North Carolina. Their arrest made national headlines, and history, as they became the first people charged with a felony for stealing Venus flytrap plants (Dionaea muscipula) from the wild.


Yes, Venus flytrap poaching is a thing. Not only that, it threatens the existence of this iconic but endangered carnivorous plant in the wild. The four men arrested this month had 970 Venus flytraps in their possession—almost 3 percent of the entire species’s naturally growing population.


Although Venus flytraps appear for sale in greenhouses around the world, they actually have an extremely limited wild range: about 120 kilometers around Wilmington, N.C.—and, even there, they remain rare. The plants grow only in bogs and many of their habitats have been lost to development over the past century. Flytraps disappeared in other locations after fire-suppression techniques protected properties but allowed brush to thrive, starving the plants of the sunlight they needed to flourish. Today Venus flytraps only survive on a handful of sites, all of which are owned by The Nature Conservancy, the North Carolina government or the U.S. military.


Over the past decades The Nature Conservancy has managed to protect flytraps from development and fire-suppression schemes. Poaching, however, has remained a persistent problem. “We’ve had flytraps poached on our land,” says Debbie Crane, director of communications for The Nature Conservancy’s North Carolina chapter, who says thefts of a thousand plants at a time were all too common. The crime, until last December, was considered to be a mere misdemeanor with a maximum $50 fine. “People would get a slap on the hand in court, and they didn’t care,” Crane says. “They came out of court grinning.”


A new law that went into effect on December 1 should help change that. Stealing Venus flytraps is now a felony, punishable by 25 to 39 months in jail—a penalty the four men arrested this month will face if convicted. “What makes poaching so sad and stupid is that the people who are doing it are local folks,” Crane says. “They’re not making much money off of it. They’re selling the bulbs for maybe 25 cents. It’s an incredibly stupid thing that they’re going to wipe out this wonderful thing in nature.”

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Ohio Wetlands Association's curator insight, February 11, 8:25 AM

The Venus Flytrap is an iconic wetland plant. Make sure you only buy greenhouse grown plants. Leave those in the wild to be wild.

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Snakes are 70 million years older than scientists previously thought

Snakes are 70 million years older than scientists previously thought | Amazing Science | Scoop.it

A new look at four fossils has revealed that snakes’ earliest known ancestor lived as many as 70 million years earlier than thought, scientists said Tuesday. Until now, the fossil record had suggested snakes slithered onto the scene in the Upper Cretaceous period, about 94-100 million years ago.


But an international team of researchers reported in the journal Nature Communications that serpents actually have a much longer lineage. Evolution of ‘snakes’ is much more complex than previously thought,” Michael Caldwell, a professor at the University of Alberta in Canada, said in a press release. Re-analysing fossils in museum collections, the scientists found that the oldest among them belonged to the earliest identifiable snake, which lived between 143 and 167 million years ago.


The granddaddy is a critter dubbed Eophis underwoodi, after Garth Underwood, an expert at Britain’s Natural History Museum, who wrote an important reference work on snakes in the 1960s. E. underwoodi lived in the Middle Jurassic period, during the final stage of an important event in Earth’s geological history — the breakup of the Pangaea supercontinent into two components called Gondwana and Laurasia.


It, and the three other ancient fossils, suggest that snakes by this time had already differentiated from their lizard cousins, the study says.

The big giveaway is the skull, which remains almost unchanged among snakes to this day.

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