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Neurologists Engineer First System of Human Nerve-Cell Tissue
2008-03-23 11:02:00
Researchers at the University of Pennsylvania School of Medicine have demonstrated that living human nerve cells can be engineered into a network that could one day be used for transplants to repair damaged to the nervous system. They report their findings in the February issue of the Journal of Neurosurgery.?We have created a three-dimensional neural network, a mini nervous system in culture, which can be transplanted en masse,? explains senior author Douglas H. Smith, MD, Professor, Department of Neurosurgery and Director of the Center for Brain Injury and Repair at Penn.Although neuron transplantation to repair the nervous system has shown promise in animal models, there are few sources of viable neurons for use in the clinic and insufficient approaches to bridge extensive nerve damage in patients.The Stretch TestIn previous work, Smith?s group showed that they could induce tracts of nerve fibers called axons to grow in response to mechanical tension. They placed neurons from rat...
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NASA Satellite Detects Record Gamma Ray Burst Explosion Halfway Across Univ
2008-03-21 11:27:00
A powerful stellar explosion detected March 19 by NASA's Swift satellite has shattered the record for the most distant object that could be seen with the naked eye.The explosion was a gamma ray burst. Most gamma ray bursts occur when massive stars run out of nuclear fuel. Their cores collapse to form black holes or neutron stars, releasing an intense burst of high-energy gamma rays and ejecting particle jets that rip through space at nearly the speed of light like turbocharged cosmic blowtorches. When the jets plow into surrounding interstellar clouds, they heat the gas, often generating bright afterglows. Gamma ray bursts are the most luminous explosions in the universe since the big bang."This burst was a whopper," said Swift principal investigator Neil Gehrels of NASA's Goddard Space Flight Center in Greenbelt, Md. "It blows away every gamma ray burst we've seen so far."Swift's Burst Alert Telescope picked up the burst at 2:12 a.m. EDT, March 19, and pinpointed the coordinate...
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UC San Diego Chemists Find Important Contributor to Smog
2008-03-21 11:24:00
Chemists at the University of California, San Diego have discovered that a chemical reaction in the atmosphere above major cities long assumed to be unimportant in urban air pollution is in fact a significant contributor to urban ozone?the main component of smog.Their finding, detailed in the March 21 issue of the journal Science, should help air quality experts devise better strategies to reduce ozone for the more than 300 counties across the United States with ozone levels that exceed new standards announced last week by the Environmental Protection Agency. It should also benefit cities in the rest of the world such as Mexico City and Beijing that are now grappling with major air quality and urban smog problems. More than 100 million people worldwide currently live in cities that fail to meet international standards for air quality. ?This study provides us with additional insight into the chemistry of urban ozone production,? said Amitabha Sinha, a professor of chemistry and...
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Breast cancer gene carriers? risk ?amplified? by additional genes
2008-03-21 11:22:00
Many women with a faulty breast cancer gene could be at greater risk of the disease due to extra ?risk amplifying? genes, according to research published in this week in the American Journal of Human Genetics. Cancer Research UK scientists, including lead author Professor Doug Easton at the University of Cambridge, have found that common versions of two genes ? FGFR2 and TNRC9 ? known to increase breast cancer risk in the general population - also increase the risk in women carrying damaged versions of the BRCA2 gene. Around one in eighteen women will develop breast cancer by the age of 65. On average, half of women carrying a faulty BRCA2 gene will develop the disease by the age of 70. This study found that particular combinations of the FGFR2 and TNRC9 genes modify the breast cancer risk in BRCA2 mutation carriers. Around twenty percent of the BRCA2 mutation carriers have the lowest risk combination of the FGFR2 and ...
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Researchers develop method to rapidly ID optimal drug cocktails
2008-03-18 21:04:00
UCLA researchers have developed a feedback control scheme that can search for the most effective drug combinations to treat a variety of conditions, including cancers and infections. The discovery could play a significant role in facilitating new clinical drug-cocktail trials. The best known use of drug cocktails has been in the fight against HIV, the virus that causes AIDS. Drug cocktails also have been used to combat several types of cancer. Often, drugs that might not be effective in combating diseases individually do much better in combination. With the use of the new closed-loop feedback control scheme, an approach guided by a stochastic search algorithm, researchers at the UCLA Henry Samueli School of Engineering and Applied Science and UCLA's Jonsson Comprehensive Cancer Center have devised an invaluable means of identifying potent drug combinations fast and efficiently. Their findings appear in the March 17 online version of the journal Proceedings of the National Academy...
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UA Mirror Lab to Cast Two Mirrors in One for the LSST
2008-03-17 22:21:00
The University of Arizona's Steward Observatory Mirror Laboratory is about to cast a new kind of giant optic for a unique wide-field survey telescope, the Large Synoptic Survey Telescope. The telescope will be the widest, fastest, deepest eye of the new digital age. Mirror Lab workers will begin loading 51,900 pounds of glass into the mirror mold early today. The Mirror Lab will cast two mirrors as a single piece of glass for the telescope, known as the LSST, this month. The lab will cast an outer 27-foot-diameter (8.4 meter) primary mirror and an inner 16.5-foot-diameter (5 meter) third mirror in one mold. It is the first time a combined primary and tertiary mirror will be produced on such a large scale.The LSST will be the world's largest, most powerful wide-angle survey telescope. It will provide time-lapse digital imaging across the entire available night sky every three days, enabling astronomers anywhere simultaneous access to study supernovae, planet-approaching asteroid...
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Physicists discover how fundamental particles lose track of quantum mechani
2008-03-16 21:09:00
Science Express, the advance online publication of the journal Science, researchers report a series of experiments that mark an important step toward understanding a longstanding fundamental physics problem of quantum mechanics. The scientists presented their findings at the annual meeting of the American Physical Society here this week. The problem the physicists addressed is how a fundamental particle in matter loses track of its quantum mechanical properties through interactions with its environment. The research was performed by scientists at the California NanoSystems Institute at the University of California, Santa Barbara and the U. S. Department of Energy Ames Laboratory in Iowa. At the quantum level things like particles or light waves behave in ways very different from what scientists expect in a human-scale world. In the quantum world, for example, an electron can exist in two places at the same time, what is called a "superposition" of states, or spin up and down at the ...
More About: Physics , Track , Fundamental , Quantum , Discover

Potential Alzheimer?s Disease Drug Target Identified
2008-03-15 11:06:00
In findings with the potential to provide a therapy for Alzheimer ?s disease patients where none now exist, a researcher at the University of California, San Diego and colleagues have demonstrated in mice a way to reduce the overproduction of a peptide associated with the disease. The study, which showed substantial improvement in memory in an animal model of Alzheimer?s disease, was led by Vivian Y. H. Hook, Ph.D., professor of the Skaggs School of Pharmacy and Pharmaceutical Sciences and professor of neurosciences, pharmacology and medicine at the UCSD School of Medicine, together with American Life Science Pharmaceuticals of San Diego. The study will be published in the March 21 edition of the Journal of Biological Chemistry, online March 14. A hallmark sign of Alzheimer?s disease, seen during autopsy of a patient?s brain, is the accumulation of amyloid plaque deposits composed primarily of the neurotoxic beta-amyloid (A?) peptide which is believed to be a major factor in ...
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Voting for more than just either-or
2008-03-15 11:04:00
Traditional voting systems only allow people to make a single choice -- a limitation many voters find frustrating, particularly when there is a crowded field of candidates as there was early in the current presidential nominating cycle. But it doesn't have to be that way.Alternative voting systems, which allow people to rank their preferences in order instead of simply picking one, have been known for centuries, but have been devilishly difficult to implement and often result in a very slow tallying of results. One example is the system used in the Iowa caucuses, in which supporters of candidates who fail to reach a certain threshold in the first round can then move on to their second choices, and so on until a clear winner emerges.A new computer software system developed by MIT researchers promises to make such ranking systems just as easy as traditional voting -- and to give results that leave more people satisfied. The system is about to get its first mass-market trial with the ...
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Physicists discover how fundamental particles lose track of quantum mechani
2008-03-14 10:34:00
In today?s Science Express, the advance online publication of the journal Science, researchers report a series of experiments that mark an important step toward understanding a longstanding fundamental physics problem of quantum mechanics. The scientists presented their findings at the annual meeting of the American Physical Society here this week. The problem the physicists addressed is how a fundamental particle in matter loses track of its quantum mechanical properties through interactions with its environment. The research was performed by scientists at the California NanoSystems Institute at the University of California, Santa Barbara and the U. S. Department of Energy Ames Laboratory in Iowa. At the quantum level things like particles or light waves behave in ways very different from what scientists expect in a human-scale world. In the quantum world, for example, an electron can exist in two places at the same time, what is called a ?superposition? of states, or spin up an...
More About: Physics , Track , Particle , Fundamental , Quantum

A Protein that Triggers Aggressive Breast Cancer
2008-03-14 10:31:00
SATB1 is a nuclear protein well known for its crucial role in regulating gene expression during the differentiation and activation of T cells, making it a key player in the immune system. But SATB1 has now revealed a darker side: it is an essential contributing factor in the most aggressive forms of breast cancer. SATB1 forms a three-dimensional cage-like structure within the cell nucleus (left) that binds to DNA specific sites within genes, reorganizes chromatin, and recruits enzymes that promote the expression or suppression of genes (right). Breast cancer cells need SATB1 to become metastatic; metastasis ? the stage when cells break away from the original tumor and spread to other parts of the body ? is the final step of solid tumor progression and is the most common cause of death in cancer patients. "In breast tumors, SATB1 reprograms...
More About: Cancer , Breast Cancer , Protein , Triggers

Strength Is But Skin Deep at the Nanoscale
2008-03-13 21:01:00
For centuries, engineers have bent and torn metals to test their strength and ductility. Now, materials scientists at the University of Pennsylvania School of Engineering and Applied Science are studying the same metals but at nanoscale sizes in the form of wires a thousand times thinner than a human hair. This work has enable Penn engineers to construct a theoretical model to predict the strength of metals at the nanoscale. Using this model, they have found that, while metals tend to be stronger at nanoscale volumes, their strengths saturate at around 10-50 nanometers diameter, at which point they also become more sensitive to temperature and strain rate. Such prediction of different strength regimes of nano-solids is important for future application and engineering design of nanotechnology.Such small-volume materials with relatively large surface areas are now routinely employed in microchips and nanoscience and technology, and their mechanical properties can differ vastly from th...
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On a 'roll': MIT researchers devise new cell-sorting system
2008-03-13 10:07:00
Capitalizing on a cell's ability to roll along a surface, MIT researchers have developed a simple, inexpensive system to sort different kinds of cells--a process that could result in low-cost tools to test for diseases such as cancer, even in remote locations.Rohit Karnik, an MIT assistant professor of mechanical engineering and lead author of a paper on the new finding appearing last week in the journal Nano Letters, said the cell-sorting method was minimally invasive and highly innovative."It's a new discovery," he said. "Nobody has ever done anything like this before." The method relies on the way cells sometimes interact with a surface (such as the wall of a blood vessel) by rolling along it. In the new device, a surface is coated with lines of a material that interacts with the cells, making it seem sticky to specific types of cells. The sticky lines are oriented diagonally to the flow of cell-containing fluid passing over the surface, so as certain kinds of cells respond to...
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Biologists identify key protein in cell?s 'self-eating' function
2008-03-12 10:53:00
Molecular biologists at the University of California, San Diego have found one piece of the complex puzzle of autophagy, the process of ?self-eating? performed by all eukaryotic cells -- cells with a nucleus -- to keep themselves healthy. Their finding, published in the March 11 issue of the journal Developmental Cell , is important because it allows scientists to control this one aspect of cellular autophagy, and may lead to the ability to control other selective ?self-eating? processes. This, in turn, could help illuminate autophagy?s role in aging, immunity, neurodegeneration and cancer. All eukaryotic cells dispose of bacteria, viruses, damaged organelles and other non-essential components through this self-eating process. A part of the cell called the lysosome engulfs and degrades subcellular detritus. The ability of cells to recycle and reuse the cellular raw materials, as well as to ?re-model? themselves in response to changing conditions, allows them to ad...
More About: Protein , Eating , Function

Microchip fingerprints used to lock out chip pirates
2008-03-12 10:52:00
Pirated microchips -- chips stolen from legitimate factories or made from stolen blueprints -- account for billions of dollars in annual losses to chipmakers. But a series of novel techniques developed at Rice University over the past year could stop pirates by allowing chip designers to lock and remotely activate chips with a unique ID tag. When a chip is locked with the new technology, only the patent-holder can decipher the key and activate the chip -- meaning knockoffs and stolen chips are worthless. "Ours is the first remote-activation scheme that protects integrated circuits against piracy by exploiting their inherent, unclonable variability," said the technology's original inventor, Farinaz Koushanfar, assistant professor in electrical and computer engineering at Rice. "We use slight variations that arise in modern manufacturing to create a unique, digital identification that acts like a fingerprint for each chip, and we integrate that into the chip's functionality." The...
More About: Pirates , Computer , Lock , Chip

Short-term stress can affect learning and memory
2008-03-12 10:47:00
Short-term stress lasting as little as a few hours can impair brain-cell communication in areas associated with learning and memory, University of California, Irvine researchers have found.It has been known that severe stress lasting weeks or months can impair cell communication in the brain?s learning and memory region, but this study provides the first evidence that short-term stress has the same effect. The study appears in the March 12 edition of the Journal of Neuroscience.?Stress is a constant in our lives and cannot be avoided,? said Dr. Tallie Z. Baram, the Danette Shepard Chair in Neurological Sciences in the UC Irvine School of Medicine and study leader. ?Our findings can play an important role in the current development of drugs that might prevent these undesirable effects and offer insights into why some people are forgetful or have difficulty retaining information during stressful situations.?In their study, Baram and her UC Irvine colleagues identified a novel process ...
More About: Memory , Learning , Short-term , Brain

Policing cells demand ID to tell friend from foe, say University of Pennsyl
2008-03-11 21:39:00
University of Pennsylvania scientists studying macrophages, the biological cells that spring from white blood cells to eat and destroy foreign or dying cells, have discovered how these ?policemen? differentiate between friend and foe. The paper appears as the cover article in the March 10 edition of the Journal of Cell Biology. The knowledge suggests new ways science may be able to turn off rogue macrophages that are the root cause of the many inflammatory diseases ranging from atherosclerosis to arthritis and that provide the mechanism for tissue and organ rejection after transplant. There is also evidence that some types of cancer cells over-express the molecular protein that macrophages recognize as friendly ? like a fake ID ? which allows the cancer to avoid being perceived as foreign. In addition, the molecules involved in the recognition mechanism appear somewhat variable from person to person, with possible links to success or failure in transplantation of stem cells. Resea...
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Protein in Embryonic Stem Cells Controls Malignant Tumor Cells
2008-03-11 21:31:00
A protein that governs development of human embryonic stem cells (hESCs) also inhibits the growth and spread of malignant melanoma, the deadliest skin cancer, Northwestern University researchers have discovered. Metastatic melanoma, which develops from the transformation of skin pigment cells or melanocytes, has a death rate of more than 80 percent and a median survival of less than 7.5 months.The Northwestern scientists, led by researcher Mary J. C. Hendrix, additionally found that the protein, called Lefty, prevents aggressive breast cancer cells from metastasizing. Death from metastatic breast cancer exceeded 40,000 in 2007, with over 180,000 new cases diagnosed in the United States.Importantly, Lefty is secreted only in hESCs, and not in any other stem cell type tested ? including stem cells isolated from amniotic fluid, cord blood or adult bone marrow ? or placental cells.Results of the study, described in an article in the March 3rd online version of The Proceedings of the Na...
More About: Tumor , Protein , Stem Cells , Genetics , Stem

Shell shock
2008-03-11 21:27:00
An MIT materials scientist's research on sea snails has helped transform battery technology and may end the era when cell phones die if they're dropped and PDAs must be replaced if they get dunked in the tub. Thanks to those sea snails and a eureka moment, Angela Belcher, Germeshausen Professor of Materials Science and Engineering and Biological Engineering, is developing smart nano-materials--hybrids of organic and inorganic components--beginning with a rechargeable, biologically based battery that looks like plastic food wrap.Belcher's eureka moment occurred 10 years ago; it arose from her long, delighted fascination with abalone, the sea snail, and from her willingness to ask a wide-open question, "What if?"Holding up an abalone shell before a visitor, Belcher describes the moment when the two threads--persistent interest and sudden insight--came together, forming the basis of her current research, which spans inorganic chemistry, materials chemistry, biochemistry, molecular b...
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New UC analysis shows alarming increase in expected growth of China's CO2 e
2008-03-11 10:27:00
The growth in China 's carbon dioxide (CO2) emissions is far outpacing previous estimates, making the goal of stabilizing atmospheric greenhouse gases much more difficult, according to a new analysis by economists at the University of California, Berkeley, and UC San Diego. Previous estimates, including those used by the Intergovernmental Panel on Climate Change, say the region that includes China will see a 2.5 to 5 percent annual increase in CO2 emissions, the largest contributor to atmospheric greenhouse gases, between 2004 and 2010. The new UC analysis puts that annual growth rate for China to at least 11 percent for the same time period. The study is scheduled for print publication in the May issue of the Journal of Environmental Economics and Management, but is now online. The researchers' most conservative forecast predicts that by 2010, there will be an increase of 600 million metric tons of carbon emissions in China over the country's levels in 2000. This growth f...
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Scientists determine structure of brain receptor implicated in epilepsy and
2008-03-10 15:25:00
Scientists funded by the Biotechnology and Biological Sciences Research Council (BBSRC) have published new research in the journal Molecular Pharmacology identifying the structure of a receptor in the brain implicated in conditions such as epilepsy and pre-menstrual tension. The same receptor has also been reported to be highly sensitive to alcohol. The University of Cambridge team, in collaboration with colleagues at Aston University and the University of Alberta, have determined the arrangement of the constituent parts of an uncommon but important type of GABA receptor in the brain. GABAA receptors in the central nervous system play important roles in the body?s response to gamma-aminobutyric acid (GABA), a chemical used by the brain to control certain functions. By understanding how the receptors? sub-units are arranged, scientists may now be able to develop drugs to block or stimulate them, providing hope for sufferers of a range of conditions. Different types of GABAA recepto...
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New discovery at Jupiter could help protect Earth-orbit satellites
2008-03-10 15:23:00
Radio waves accelerate electrons within Jupiter's magnetic field in the same way as they do on Earth Radio waves accelerate electrons within Jupiter?s magnetic field in the same way as they do on Earth, according to new research published in Nature Physics this week. The discovery overturns a theory that has held sway for more than a generation and has important implications for protecting Earth-orbiting satellites. Using data collected at Jupiter by the Galileo spacecraft, Dr Richard Horne of British Antarctic Survey (BAS) and colleagues from the University of California, Los Angeles, and the University of Iowa found that a special type of very low frequency radio wave is strong enough to accelerate electrons up to very high energies inside Jupiter?s magnetic field. According to lead author, Dr Richard Horne, ?We?ve shown before that very low frequency radio waves can accelerate electrons in the Earth?s magnetic field, but we have now shown that exactly the same theory works...
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Genetic research unveils common origins for distinct clinical diagnoses
2008-03-09 19:34:00
Researchers at Johns Hopkins have discovered that two clinically different inherited syndromes are in fact variations of the same disorder. Reporting in the April issue of Nature Genetics , the team suggests that at least for this class of disorders, the total number and ?strength? of genetic alterations an individual carries throughout the genome can generate a range of symptoms wide enough to appear like different conditions. ?We?re finally beginning to blur the boundaries encompassing some of these diseases by showing that they share the same molecular underpinnings,? says Nicholas Katsanis, Ph.D., an associate professor of ophthalmology at the McKusick-Nathans Institute of Genetic Medicine at Hopkins. ?This is important progress for several reasons. First, knowing what?s going on molecularly and being able to integrate rarer conditions under common mechanisms allows us to potentially help more people at once. Second, clinicians can finally begin to offer more accurate diagnoses...
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Light echoes whisper the distance to a star
2008-03-09 13:12:00
Astronomers calibrate the distance scale of the Universe Taking advantage of the presence of light echoes, a team of astronomers have used an ESO telescope to measure, at the 1% precision level, the distance of a Cepheid - a class of variable stars that constitutes one of the first steps in the cosmic distance ladder."Our measurements with ESO's New Technology Telescope at La Silla allow us to obtain the most accurate distance to a Cepheid," says Pierre Kervella, lead-author of the paper reporting the result. Cepheids [1] are pulsating stars that have been used as distance indicators since almost a hundred years. The new accurate measurement is important as, contrary to many others, it is purely geometrical and does not rely on hypotheses about the physics at play in the stars themselves.The team of astronomers studied RS Pup, a bright Cepheid star located towards the constellation of Puppis ('the Stern') and easily visible with binoculars. RS Pup varies in brightness by almost...
More About: Space , Astronomy , Star , Light , Echoes

WMAP Reveals Neutrinos, End of Dark Ages, First Second of Universe
2008-03-08 22:56:00
NASA released this week five years of data collected by the Wilkinson Microwave Anisotropy Probe (WMAP) that refines our understanding of the universe and its development. It is a treasure trove of information, including at least three major findings:New evidence that a sea of cosmic neutrinos permeates the universe Clear evidence the first stars took more than a half-billion years to create a cosmic fog Tight new constraints on the burst of expansion in the universe's first trillionth of a second"We are living in an extraordinary time," said Gary Hinshaw of NASA's Goddard Space Flight Center in Greenbelt, Md. "Ours is the first generation in human history to make such detailed and far-reaching measurements of our universe."WMAP measures a remnant of the early universe - its oldest light. The conditions of the early times are imprinted on this light. It is the result of what happened earlier, and a backlight for the later development of the universe. This light lost energy as the ...
More About: Universe , Physics , Dark , Nasa

MIT researchers demonstrate protective role of microRNA
2008-03-08 22:54:00
Snippets of genetic material that have been linked to cancer also play a critical role in normal embryonic development in mice, according to a new paper from MIT cancer biologists. The work, reported in the March 7 issue of Cell, shows that a family of microRNAs--short strands of genetic material--protect mouse cells during development and allow them to grow normally. But that protective role could backfire: The researchers theorize that when these microRNAs become overactive, they can help keep alive cancer cells that should otherwise die--providing another reason to target microRNAs as a treatment for cancer.Discovered only a decade ago, microRNAs bind to messenger RNAs (mRNAs), preventing them from delivering protein assembly instructions, thereby inhibiting gene expression. The details of how microRNAs act are not yet fully understood."The scientific community is busy trying to understand what specific biological functions these microRNAs affect," said Andrea Ventura, lead autho...
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Language of a fly proves surprising
2008-03-08 22:50:00
A group of researchers has developed a novel way to view the world through the eyes of a common fly and partially decode the insect?s reactions to changes in the world around it. The research fundamentally alters earlier beliefs about how neural networks function and could provide the basis for intelligent computers that mimic biological processes. In an article published in the Public Library of Science Computational Biology Journal, Los Alamos physicist Ilya Nemenman joins Geoffrey Lewen, William Bialek and Rob de Ruyter van Steveninck of the Hun School of Princeton, Princeton University and Indiana University, respectively, in describing the research. The team used tiny electrodes to tap into motion-sensitive neurons in the visual system of a common blowfly. Neurons are nerve cells that emit tiny electric spikes when stimulated. The electrodes detected pulses from the motion-sensitive neurons in the fly. The fly uses the neurons to estimate, and subsequently control, how it mov...
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HIV Blocked
2008-03-02 13:14:00
Virus infections remain the single most common reason that Canadians seek medical attention. Although impressive progress has been made in developing anti-viral drugs, drug resistant variants often arise and many virus infections remain untreatable. The innate immune system is our first line of defense against virus infection. Unfortunately, most viruses produce proteins that serve as effective countermeasures. My laboratory is focused on how viral regulatory proteins function at the molecular level, and how cellular antiviral responses inhibit viral replication. The hope is that increased understanding of host antiviral defenses and viral immune evasion strategies will open up new approaches to controlling virus infections. Most of our work focuses on herpes simplex virus (HSV), a ubiquitous human pathogen and the prototypical member of the herpesviridae, a large family of enveloped DNA viruses that replicate in the nuclei of host cells. Recently we have also begun similar studies ...

Dirty Space and Supernovae
2008-03-02 13:11:00
Interstellar space may be strewn with tiny whiskers of carbon, dimming the light of far-away objects. This discovery by scientists at the Carnegie Institution may have implications for the ?dark energy? hypothesis, proposed a decade ago in part to explain the unexpected dimness of certain stellar explosions called Type1a supernovae. Type1a supernovae are among the brightest objects in the universe. Astronomers use them as ?standard candles? to gauge cosmological distances: brighter-appearing supernovae are closer, dimmer ones are farther away. In the late 1990s some astronomers noticed that some seemed too dim?too far away?to be explained by conventional theories of the universe?s expansion. This led to the hypothesis that the expansion was accelerating, pushed along by an unknown form of energy ? dark energy. In the current study, published online February 28 inScience Express, Andrew Steele and Marc Fries of the Carnegie Institution?s Geophysical Laboratory report th...
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Device allows scientists to control gene activity across generations of cel
2008-03-01 11:03:00
Just as cells inherit genes, they also inherit a set of instructions that tell genes when to become active, in which tissues and to what extent. Now, Rockefeller University researchers have built a device that, by allowing scientists to turn genes on and off in actively multiplying budding yeast cells, will help them figure out more precisely than before how genes and proteins interact with one another and how these interactions drive cellular functions.?A slight disturbance in the abundance of a single protein can affect the functioning of a cell dramatically,?? says Gilles Charvin, a postdoc who works with both Eric Siggia, head of the Laboratory of Theoretical Condensed Matter Physics, and Frederick Cross, headof the Laboratory of Yeast Molecular Gene tics. ?So, we wanted to devise a way to supply a single cell with a controlled pulse of protein at any time and then see how the cell would respond,?? he says.Although scientists have had the tools to track single cells and measure t...
More About: Scientists , Device , Control , Generations