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POPSViruses can catch colds, says study that redefines life itself Prof La Scola and his colleagues were surprised to spot a smaller type of virus attached to the virus-making factory inside infected cells. The new virus - Sputnik - was unable to infect cells by itself but seemed to hijack the larger to achieve its infectious aims. By regulating the growth and death of plankton, giant viruses - and satellite viruses such as Sputnik - could be a major influence on ocean nutrient cycles and climate. "These viruses could be major players in global systems," Nature is told by Prof Curtis Suttle, an expert in marine viruses at the University of British Columbia in Vancouver.
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POPSHow one day we may all be eternally young "We found a normal developmental programme that works in young animals, but becomes unbalanced as the worm gets older. It accounts for the lion's share of molecular differences between young and old worms." If ageing is not a cost of unavoidable chemistry, but is instead driven by changes in regulatory genes, the ageing process may not be inevitable, he added.
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POPSThe More We Know About Genes, the Less We Understand About 95 percent of the rewired bacteria did just fine with their new networks. They went on with their lives, feeding, growing and dividing. Some even performed better than microbes with the original wiring, under some conditions. The tolerance these bacteria showed reveals something important about how evolution works. Humans can randomly rewire cells, and so can mutations. There's something about gene networks that allow them to thrive despite these mutations, and, in some cases, to even gain an edge in the evolutionary race.
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POPSBacteria provide horsepower for tiny motor When bacteria crawl clockwise in the circular groove underlying this motor, they brush past the tabs that support the motor's star-shaped rotor. Molecular bonds between the microbes and a coating on the rotor tug the device around.
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POPSThe Secret Of Fast Complex Brain Restructuring Up to now, it had been assumed that nerve cells can only exchange information via the synapses which are special contact points. However, synapses require up to two days to become fully functional - a waste of time and energy if the contact is to be broken down again. The brain could take almost 1000 years to develop if a synapse had to mature at each cell contact. It appears that nerve cells can also obtain information about their neighbours even without a synapse. Neurobiologists Christian Lohmann and Tobias Bonhoeffer from the Max Planck Institute for Neurobiology have now explained how they do that. The secret to how the information is exchanged: local calcium signals very quickly transmit all the necessary information to the cell. A synapse only actually develops when the cell and the contact point prove to be suitable candidates for long-term contact.
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POPSNew Mode Of Gene Regulation Discovered In Mammals As research advances, the more it becomes clear, that gene regulation networks are actually complex computing machines. DNA is not a mere repository of information. What's more, the newly discovered mechanism is self referential, which adds another later of complexity to gene regulation processes.
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POPS15 Answers to Creationist Nonsense (Please follow the link to this article and read it completely before you comment on it. Thanks) It is funny how religious people will demand proof of evolution while they have no proof nor will ever have proof of any aspect of their beliefs.
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POPSPrevailing theory of aging challenged in Stanford worm study To see whether these signal molecules were part of a wear-and-tear aging mechanism, the researchers exposed worms to stresses thought to cause aging, such as heat (a known stressor for nematode worms), free-radical oxidation, radiation and disease. But none of the stressors affected the genes that make the worms get old. So it looked as though worm aging wasn’t a storm of chemical damage. Instead, Kim said, key regulatory pathways optimized for youth have drifted off track in older animals. Natural selection can’t fix problems that arise late in the animals’ life spans, so the genetic pathways for aging become entrenched by mistake. Kim’s team refers to this slide as “developmental drift.”
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POPSGene silencer and quantum dots reduce protein production to a whisper
Each quantum dot was surrounded by a proton sponge that carried a positive charge. Without any quantum dots attached, the siRNA's negative charge would prevent it from penetrating a cell's wall. With the quantum-dot chaperone, the more weakly charged siRNA complex crosses the cellular wall, escapes from the endosome (a fatty bubble that surrounds incoming material) and accumulates in the cellular fluid, where it can do its work disrupting protein manufacture. Key to the newly published approach is that researchers can adjust the chemical makeup of the quantum dot's proton-sponge coating, allowing the scientists to precisely control how tightly the dots attach to the siRNA. Quantum dots were dramatically better than existing techniques at stopping gene activity. In experiments, a cell's production of a test protein dropped to 2 percent when siRNA was delivered with quantum dots. By contrast, the test protein was produced at 13 percent to 51 percent of normal levels when the siRNA
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POPSResearchers turn one form of adult mouse cell directly into another Joan Brugge, Chair of the Department of Cell Biology at Harvard Medical School, said the new study "provides exciting new insights into yet another aspect of cell plasticity that was not appreciated previously and that offers great potential therapeutically. Direct reprogramming represents a more straight-forward strategy to treat diseases involving loss of function of specific cell populations than approaches requiring an intermediate embryonic stem cell," she said.
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POPSGenetically engineered cells make their own nanomagnets, providing clear MRI images. If genetically engineering cells to produce their own magnetic nanoparticles proves successful, this provides a new window through which to view many biological processes as they unfold, from the formation of tumors to the migration of stem cells injected to treat disease. "It's just amazing that they can get a mammalian cell to actually make the material," says Lee Josephson, an associate professor at the Harvard Medical School's Center for Molecular Imaging Research. "I think it's a really meaningful piece of work."
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POPSFuture for clean energy lies in 'big bang' of evolution For humans now there is the tantalising possibility of tweaking the photosynthetic reactions of cyanobacteria to produce fuels we want such as hydrogen, alcohols or even hydrocarbons, rather than carbohydrates. Progress at the research level has been rapid, boosting prospects of harnessing photosynthesis not just for energy but also for manufacturing valuable compounds for the chemical and biotechnology industries. Such research is running on two tracks, one aimed at genetically engineering real plants and cyanobacteria to yield the products we want, and the other to mimic their processes in artificial photosynthetic systems built with human-made components. Both approaches hold great promise and will be pursued in parallel, as was discussed at a recent workshop focusing on the photosynthetic reaction centres of cyanobacteria, organised by the European Science Foundation (ESF).
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POPSNewly described 'dragon' protein could be key to bird flu cure This unexpected relationship between the two subunits could inspire a number of different therapies or vaccines for H5N1 that rely on muzzling the "dragon's" jaws with another molecule or chemical compound that would block the PB1 subunit's access to the PA site, according to Joachimiak. "If we can put a bit in the dragon's mouth, we can slow or even potentially someday stop the spread of avian flu," he said. "Since we are talking about a relatively small protein surface area, finding a way to inhibit RNA replication in H5N1 seems very feasible."
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POPSTermites are actually social cockroaches: study DNA analysis reveals some unexpected relationships among animals, including this startling discovery: The order Isoptera is no more--termites are now more properly classified as members of Order Blattodea, along with the cockroaches. Remarkable creatures, all.
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POPSResearchers Discover Remnant of an Ancient 'RNA World' Breaker's lab solved a decades-old mystery by describing how tiny circular RNA molecules called cyclic di-GMP are able to turn genes on and off. This process determines whether the bacterium swims or stays stationary, and whether it remains solitary or joins with other bacteria to form organic masses called biofilms. Bacterial use of RNA to trigger major changes without the involvement of proteins resolves one of the questions about the origin of life: If proteins are needed to carry out life's functions and DNA is needed to make proteins, how did DNA arise? The answer is what Breaker and other researchers call the RNA World. They believe that billions of years ago, single strands of nucleotides that comprise RNA were the first forms of life and carried out some of the complicated cellular functions now done by proteins. The riboswitches are highly conserved in bacteria, illustrating their importance and ancient ancestry, Breaker said.
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POPSTHE ORIGIN OF BIOLOGICAL INFORMATION Yet Muller and Newman insist that population genetics, and thus evolutionary biology, has not identified a specifically causal explanation for the origin of true morphological novelty during the history of life. Central to their concern is what they see as the inadequacy of the variation of genetic traits as a source of new form and structure. They note, following Darwin himself, that the sources of new form and structure must precede the action of natural selection (2003:3)–that selection must act on what already exists. Yet, in their view, the “genocentricity” and “incrementalism” of the neo-Darwinian mechanism has meant that an adequate source of new form and structure has yet to be identified by theoretical biologists. Instead, Muller and Newman see the need to identify epigenetic sources of morphological innovation during the evolution of life. In the meantime, however, they insist neo-Darwinism lacks any “theory of the generative”
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POPSReligion/Science - Oil/Water No matter what mental rationalization you've thought up the bottom line is that science and religion are at odds with one another. Ask anyone who has waded through the tortured reasoning of theists to reconcile their beliefs with scientific facts knows that believing in talking snakes, burning bushes, Jewish zombies, or virgin births has to forgo reality and enter a world of myth and fairy tales. Ordinarily this could be viewed as simply a character quirk. But unfortunately it has wider reaching consequences. We are dumbing down our children because of irrational belief in a bronze age culture's view of the world. In our society, ignorance is thought charming while intelligence is "elitism". How ass backwards is this?
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