Scientists in Scotland say they may have found what causes some Alzheimer's patients to develop epilepsy. The amyloid protein, which forms in clumps in patients' brains, makes nerve cells too sensitive and prone to seizures, tests in mice suggest. The cells short-circuit and fire too many electrical signals, the Journal of Neuroscience reports. If true in humans too, which the experts say is likely, it may mean some patients will need different drugs. A mainstay of treatment for Alzheimer's is a class of drugs called the cholinesterase inhibitors. They work by stopping the breakdown of acetylcholine, an important neurotransmitter associated with memory. But an unwanted effect is that this can also increase a person's susceptibility to seizures. However, medication to control seizures can also make Alzheimer's symptoms worse. A third of Alzheimer's patients have some degree of epilepsy, posing a treatment dilemma for doctors. Researcher Professor Tibor Harkany, of the University of Aberdeen, said he hoped his findings would lead to the discovery of new drugs to treat both problems with fewer side-effects. He said: "We have shown for the first time the actual cellular process that links epilepsy and Alzheimer's disease. This provides us with a new wave of understanding in Alzheimer's disease. Our findings could lead to a rethink of the type of drugs that are given to patients with Alzheimer's disease. It should be possible to design drugs to tackle the two problems of seizures and cognition at the cellular level because both share common mechanisms." (C)BBC

Keyword: Alzheimers; Epilepsy
Link ID: 12663 - Posted: 03.19.2009

By Shankar Vedantam The study would come to be called "cursed," but it started out just as Study 15. It was a long-term trial of the antipsychotic drug Seroquel. The common wisdom in psychiatric circles was that newer drugs were far better than older drugs, but Study 15's results suggested otherwise. As a result, newly unearthed documents show, Study 15 suffered the same fate as many industry-sponsored trials that yield data drugmakers don't like: It got buried. It took eight years before a taxpayer-funded study rediscovered what Study 15 had found -- and raised serious concerns about an entire new class of expensive drugs. Study 15 was silenced in 1997, the same year Seroquel was approved by the Food and Drug Administration to treat schizophrenia. The drug went on to be prescribed to hundreds of thousands of patients around the world and has earned billions for London-based AstraZeneca International -- including nearly $12 billion in the past three years. The results of Study 15 were never published or shared with doctors, even as less rigorous studies that came up with positive results for Seroquel were published and used in marketing campaigns aimed at physicians and in television ads aimed at consumers. The results of Study 15 were provided only to the Food and Drug Administration -- and the agency has strenuously maintained that it does not have the authority to place such studies in the public domain. © 2009 The Washington Post Company

Keyword: Schizophrenia
Link ID: 12662 - Posted: 06.24.2010

By Janet Raloff A little over a week ago I wrote a two-parter on software that has uncovered hundreds of instances of apparent plagiarism in biomedical science. Copycatting someone else’s work is lazy at best; more likely it’s just amoral. But the current issue of Anesthesiology News highlights an even more egregious type of fraud: blatant fabrication of medical data. In two investigative news stories, Adam Marcus describes the case against anesthesiologist Scott S. Reuben. This prominent Massachusetts pain researcher is accused of faking data that served as the basis for a minimum of 21 published medical studies. At least plagiarists “borrow” data that are ostensibly real and therefore might have some medical validity. Fabricated data benefit no one but the author who is looking to bolster his reputation by fattening his portfolio of published studies. Indeed, the potential for harm in seeding fake findings within the medical journals is substantial. They encourage an undue belief by clinicians that certain treatments will — or will not — help patients. In Reuben’s case, his publications focused on the purported benefits in prescribing non-opiate painkillers, such as celecoxib (sold as Celebrex), a drug that inhibits cyclooxygenase-2, an enzyme that triggers an inflammatory cascade of changes in the body. His studies claimed it worked well, particularly when paired with a neuropathic pain medicine pregabalin (sold as Lyrica). But these Pfizer drugs are not the only ones that Reuben claimed performed well in place of more powerful old-line painkillers. © Society for Science & the Public 2000 - 2009

Keyword: Pain & Touch
Link ID: 12661 - Posted: 06.24.2010

By Ker Than Dolphins and their close relatives that use sound to navigate can "steer" their sonar beams by merging two sound pulses together, a new study suggests. "It's the acoustic equivalent of moving your eyes without moving your head," says marine biologist Marc Lammers of the Hawaii Institute of Marine Biology at the University of Hawaii, Kaneohe. This ability may be unique in the animal kingdom, scientists say. Biologists have long known that odontocetes, or "toothed whales," a group that includes sperm whales, beluga whales, and dolphins, navigate and hunt using sonar. Like bats, they emit high-frequency clicks that bounce off objects and then interpret the echoes. Until recently, biologists believed that sonar was a bit like a pair of headlights--it could be aimed only in the direction in which the creature's head was pointed. But in 2008, Patrick Moore of Space and Naval Warfare Systems Command, a U.S. Navy research facility in San Diego, California, and colleagues found that bottlenose dolphins can sweep their echolocation beams to the left and right by about 20° without moving their heads. What Moore's team couldn't determine was just how the animals were doing it. One idea was that the dolphin manipulates a large fatty organ in its head called the melon to aim the beam. Alternatively, scientists posited that the dolphin was producing two sonar clicks separated by a slight time delay. This would cancel frequencies in certain regions of space but enhance them in others, effectively channeling the sound in a direction other than straight ahead. © 2009 American Association for the Advancement of Science.

Keyword: Hearing
Link ID: 12660 - Posted: 06.24.2010

by Ewen Callaway If the deeply devout seem less self-doubting than others, perhaps it's because religion helps them shrug off mistakes. So say researchers who found religious people exhibit lower activity than non-believers in a brain region linked to anxiety when erring on a simple test. "Religion offers an interpretative framework to understand the world. It lets you know when to act, how to act, and what to do in specific situation," says Michael Inzlicht, a neuroscientist at the University of Toronto, Scarborough, who led the new study. "It provides a kind of blueprint on how to interact with the world." Religion – and perhaps other strongly held belief systems – buffer against second-guessing decisions, he says. Inzlicht's team tested 50 university students from diverse religious and cultural backgrounds. Christians made up most participants, but his team also tested Muslims, Hindus, Buddhists and atheists. With a technique that gauges brain activity via dozens of electrodes on the scalp called electroencephalography (EEG), Inzlicht's team focused on action in a small brain area called the anterior cingulate cortex (ACC). © Copyright Reed Business Information Ltd.

Keyword: Emotions; Stress
Link ID: 12659 - Posted: 06.24.2010

Scientists have made a significant step forward in developing a test to help diagnose the early stages of Alzheimer's disease sooner and more accurately by measuring two biomarkers — tau and beta-amyloid proteins — in cerebrospinal fluid. In a new report, researchers from the Alzheimer's Disease Neuroimaging Initiative (ADNI) not only confirmed that certain changes in biomarker levels in cerebrospinal fluid may signal the onset of mild Alzheimer's, but also established a method and standard of testing for these biomarkers. ADNI is a research partnership supported primarily by the National Institute on Aging (NIA), part of the National Institutes of Health, with private sector support through the Foundation for NIH, seeking to find neuroimaging and biomarker tests that can detect Alzheimer's disease progression and measure the effectiveness of potential therapies. These are the first cerebrospinal fluid biomarker findings to be reported by ADNI, a $60-million, five-year research program launched in 2004 to observe and track changes in some 800 older people in the United States and Canada with normal cognition, mild cognitive impairment (MCI) — a condition that often precedes Alzheimer's — or the early stages of Alzheimer's. The ADNI Biomarker Core at the University of Pennsylvania's School of Medicine in Philadelphia, headed by Leslie M. Shaw, Ph.D., and John Q. Trojanowski, MD., Ph.D., led the study, which is reported online March 17 in the Annals of Neurology. "Research indicates that Alzheimer's pathology causes changes in the brain some 10 to 20 years before any symptoms appear," said NIA Director Richard J. Hodes, M.D. "This work gives researchers a systematic and reliable method to measure changes in cerebrospinal fluid biomarkers that may herald the onset of Alzheimer's disease."

Keyword: Alzheimers
Link ID: 12658 - Posted: 06.24.2010

By DONALD G. McNEIL Jr. After her stroke, Francine V. Corso, a software engineer who worked on NASA’s lunar lander, was housebound from 1992 to 2001. Her left arm was twisted up near her neck, making it difficult to pull on a blouse, and her fingers curled so rigidly that her nails buried themselves in her palm. When she finally learned to rise from her wheelchair, her contorted left leg had the so-called horse gait of many brain-injury victims — she stepped toe-downward, and then fought to keep her foot from rolling over. Now, with injections of botulinum toxin every three months, she says, “I’m completely transformed — I drive, I volunteer, I take art classes.” Her fingers are so relaxed that a manicurist can lacquer her nails red. Botulinum toxin, the wrinkle smoother best known by the brand name Botox, has many medical uses, some official and some off label. It helps dystonia victims regain control of spasming muscles, actors who struggle with flop sweat slow down the flow, and children with clubfoot avoid surgery. Its use in stroke victims is still off label — that is, it is not approved for that purpose by the Food and Drug Administration. But it is so widely accepted that Medicare and other insurers will usually reimburse for its use. Copyright 2009 The New York Times Company

Keyword: Stroke
Link ID: 12657 - Posted: 06.24.2010

By DONALD G. McNEIL Jr. MINNEAPOLIS — Ayub Abdi is a cute 5-year-old with a smile that might be called shy if not for the empty look in his eyes. He does not speak. When he was 2, he could say “Dad,” “Mom,” “give me” and “need water,” but he has lost all that. He does scream and spit, and he moans a loud “Unnnnh! Unnnnh!” when he is unhappy. At night he pounds the walls for hours, which led to his family’s eviction from their last apartment. As he is strapped into his seat in the bus that takes him to special education class, it is hard not to notice that there is only one other child inside, and he too is a son of Somali immigrants. “I know 10 guys whose kids have autism,” said Ayub’s father, Abdirisak Jama, a 39-year-old security guard. “They are all looking for help.” Autism is terrifying the community of Somali immigrants in Minneapolis, and some pediatricians and educators have joined parents in raising the alarm. But public health experts say it is hard to tell whether the apparent surge of cases is an actual outbreak, with a cause that can be addressed, or just a statistical fluke. Copyright 2009 The New York Times Company

Keyword: Autism
Link ID: 12656 - Posted: 06.24.2010

By ELISSA ELY, M.D. CAMBRIDGE, Mass. — By 35, Dr. Alice W. Flaherty had led a life of traditional overaccomplishment: undergraduate and medical degrees from Harvard, a Ph.D. in neuroscience from M.I.T., research in movement disorders, articles in leading neurological journals. Then, in 1998, she delivered stillborn twin boys. In the grief that followed, she grew manic: poetic, metaphorical and long-winded. She wrote everywhere, up and down her arm, over and under any serviceable piece of paper. She also wrote more traditionally, producing neurology handbooks, autobiographical meditations and, in 2004, a best-selling book, “The Midnight Disease: The Drive to Write, Writer’s Block and the Creative Brain” (Houghton Mifflin). Her grief eventually subsided. Her newly uncovered bipolar disorder did not — to the benefit of her patients. Dr. Flaherty, now 45, is director of the movement disorders fellowship at Massachusetts General Hospital and an assistant professor of neurology at Harvard Medical School. But those technical descriptors do not begin to capture the way she uses the racing mind of her manic phases to drive her ideas into forceful, highly personal treatments. “Doctors tend to see patients with an overtone of category,” said the writer Rose Styron, whose husband, the late novelist William Styron, was a patient of Dr. Flaherty’s. “Alice never did. She understood Bill’s depression and his movement problems. But she really understood his needs, appetites, moods, guilts, sadnesses and potential pleasures.” Copyright 2009 The New York Times Company

Keyword: Schizophrenia
Link ID: 12655 - Posted: 06.24.2010

By Jordan Lite Ever wonder how musicians manage to play in unison? Credit their brain waves: they synchronize before and while musicians play a composition, according to new research. German scientists report in BMC Neuroscience that they measured the brain waves of eight pairs of guitarists using electroencephalography (EEG) while they played a modern jazz piece called Fusion #1 (by Alexander Buck). The researchers found that the guitarists' brain waves were aligned most during three pivotal times: when they were syncing up with a metronome, when they began playing the piece and at points during the composition that demanded the most synchrony. The synchrony was most prominent in the frontal and central parts of the brain that regulate motor function. "Whenever synchrony of behavior was high, synchrony of brain waves were also high," Ulman Lindenberger, a director the Max Planck Institute for Human Development in Berlin, tells ScientificAmerican.com. But, "we can't assign a causal role to that synchronizing." While brain synchrony during a duet seems like a given, it's a mystery how it happens, says Lindenberger, a psychologist. "One could speculate that this may be related to mirror neurons, the capacity of primates and humans to imagine the action of the other person while performing actions yourself," he says. "The mirror neuron system could be active during synchronized guitar playing." © 1996-2009 Scientific American Inc.

Keyword: Hearing
Link ID: 12654 - Posted: 06.24.2010

by Anil Ananthaswamy Electrodes implanted in the brains of people with epilepsy might have resolved an ancient question about consciousness. Signals from the electrodes seem to show that consciousness arises from the coordinated activity of the entire brain. The signals also take us closer to finding an objective "consciousness signature" that could be used to probe the process in animals and people with brain damage without inserting electrodes. Previously it wasn't clear whether a dedicated brain area, or "seat of consciousness", was responsible for guiding our subjective view of the world, or whether consciousness was the result of concerted activity across the whole brain. Probing the process has been a challenge, as non-invasive techniques such as magnetic resonance imaging and EEG give either spatial or temporal information but not both. The best way to get both simultaneously is to implant electrodes deep inside the skull, but it is difficult to justify this in healthy people for ethical reasons. Now neuroscientist Raphaël Gaillard of INSERM in Gif sur Yvette, France, and colleagues have taken advantage of a unique opportunity. They have probed consciousness in 10 people who had intercranial electrodes implanted for treating drug-resistant epilepsy. © Copyright Reed Business Information Ltd

Keyword: Miscellaneous
Link ID: 12653 - Posted: 06.24.2010

by Clare Wilson Can people think themselves sick? This is what psychiatrist Simon Wessely explores. His research into the causes of conditions like chronic fatigue syndrome and Gulf war syndrome has led to hate mail, yet far from dismissing these illnesses as imaginary, Wessely has spent his career developing treatments for them. Clare Wilson asks what it's like to be disliked by people you're trying to help How might most of us experience the effects of the mind on the body? In an average week you probably experience numerous examples of how what's going on around you affects your subjective health. Most people instinctively know that when bad things happen, they affect your body. You can't sleep, you feel anxious, you've got butterflies in your stomach... you feel awful. When does that turn into an illness? Such symptoms only become a problem when people get trapped in excessively narrow explanations for illness - when they exclude any broader consideration of the many reasons why we feel the way we do. This is where the internet can do real harm. And sometimes people fall into the hands of charlatans who give them bogus explanations. Is that how chronic fatigue syndrome can start? © Copyright Reed Business Information Ltd.

Keyword: Stress
Link ID: 12652 - Posted: 06.24.2010

By LISA SANDERS, M.D. The patient lay on the bed, her eyes wide with fear as she struggled for breath. The nurse at the bedside looked almost as scared. She turned as Dr. Kennedy Cosgrove entered the hospital room and said, “I can’t get a blood pressure, doctor — her pressure is too high for me to measure.” Cosgrove felt his own blood pressure soar. Most patients in this psychiatric ward of Stevens Hospital in Edmonds, Wash., were physically healthy, and Cosgrove, a psychiatrist, hadn’t managed this type of emergency since his internship. He ordered an EKG and quickly phoned the internal-medicine doctor on call. Ten days earlier, the patient was taken to the hospital’s emergency room by the police. According to their report, she phoned her teenage son to say goodbye — she was going to take her life. He and the police found her at home, shouting, incoherent, weeping. When Cosgrove met her later that day, his first thought was that despite her erratic behavior — which wasn’t unusual in this ward — she looked different from his other patients. Her hair was well cut. Her nails were clean and manicured. She looked tired and disheveled, but she didn’t look chronically mentally ill. After introducing himself, Cosgrove asked the patient if she knew why she was there. Tears filled her eyes. She couldn’t take the disappointment of life anymore, she told him. He nodded sympathetically. She shifted restlessly on the bed. “I’ve had seven death attempts on me — by the police!” she shouted, suddenly angry. Her eyes narrowed suspiciously. “Have you heard this?” There was a conspiracy against her — organized by the state of Washington and the Boeing Company. Sometimes she could even hear them talking to her — their voices coming from inside her own brain. She laughed giddily and then became angry again. “Get out! Get out! Get out!” Copyright 2009 The New York Times Company

Keyword: Schizophrenia; Hormones & Behavior
Link ID: 12651 - Posted: 06.24.2010

A decompression chamber may help children with autism, say researchers. After 40 hours of hyperbaric treatment autistic children showed significant improvements in social interaction and eye contact compared with controls. The BMC Pediatrics study could not show if the results were long-lasting but should prompt further investigation of the treatment, the US team said. One theory is that oxygen can help reduce inflammation and improve flow of oxygen to brain tissue. Hyperbaric treatment - effectively giving high concentrations of oxygen at increased atmospheric pressure - has been shown to have some benefit in other neurological conditions such as foetal alcohol syndrome and cerebral palsy. Some studies have looked at the treatment in children with autism but they have not compared with a dummy procedure raising questions around a "placebo effect". In the latest study, carried out at six centres in the US, 62 children aged two to seven with autism were randomly assigned to receive 40 hours of treatment over a month with 24% oxygen at increased atmospheric pressure (1.3 atm) or normal air in a slightly pressurised room (1.03 atm). Children who received the treatment showed significant improvements in overall functioning, receptive language, social interaction, eye contact, and sensory or cognitive awareness. In all, 30% in the treatment group were rated by doctors as "very much improved" or "much improved" compared with 8% of those in the control group. Overall, 80% in the treatment group improved compared with 38% of controls. Study leader, Dr Dan Rossignol from the International Child Development Resource Centre, in Florida, said the use of hyperbaric therapy for autism has been gaining popularity in the US where parents can buy their own hyperbaric chamber if they have a spare $14-17,000. (C)BBC

Keyword: Autism
Link ID: 12650 - Posted: 03.14.2009

by Ewen Callaway A newly discovered gene mutation found to cause Alzheimer's disease when inherited from both parents may give protection from the disease when only one copy is inherited. The discovery may lead to a new treatment for the neurodegenerative condition. A 44-year-old man with two copies of a mutation in a gene called APP first showed signs of Alzheimer's in his mid-thirties. Yet his relatives with a single copy of the mutation – including an 88-year-old aunt – seem to be protected from the disease, new research suggests. Mimicking this single-copy condition with a drug could offer a new way of treating Alzheimer's, says Fabrizio Tagliavini, a neurologist at Carlo Besta National Neurological Institute in Milan. Tagliavini's team uncovered the mutation in a person who showed signs of early-onset Alzheimer's but who lacked mutations in other genes associated with this inherited form of the disease. Only a small percentage of Alzheimer's cases are linked to a single, inherited mutation, yet researchers have made great strides in understanding the more common late-onset form of the disease by studying these mutations. © Copyright Reed Business Information Ltd

Keyword: Alzheimers; Genes & Behavior
Link ID: 12649 - Posted: 06.24.2010

by Andy Coghlan Scans of the brains of child musicians before and after musical training have yielded compelling evidence that proficiency and skill relies on hard graft, not innate genius. Earlier studies have shown that adult musicians have different brains to adult non-musicians. But the latest results settle arguments about whether the brain differences were there from birth, or developed through practice. "This is the first paper showing differential brain development in children who learned and played a musical instrument versus those that did not," says Gottfried Schlaug of Harvard Medical School. Schlaug's team tested musically untrained six-year-olds from the Boston area, 15 of whom then received weekly keyboard lessons for 15 months, and 16 of whom didn't. When they compared magnetic resonance imaging (MRI) scans taken before and after for both groups, they found that auditory and motor areas of the brain linked respectively with hearing and dexterity grew larger only in the trainee musicians. At the end of the training period, the musicians also outperformed the others at specific tasks related to manual dexterity and discrimination of sounds. But the two groups were matched on more distantly related skills such as arithmetic. Schlaug says that the same pupils are being followed in case it takes longer for these more "distant" skills to emerge. © Copyright Reed Business Information Ltd.

Keyword: Hearing; Learning & Memory
Link ID: 12648 - Posted: 06.24.2010

Your fingertips are among the most sensitive parts of your body, and this makes them surprisingly easy to fool. Take an ordinary comb and pencil and lay your index finger along the top of the comb, then run the pencil back and forth along the side of the teeth. Even though the teeth are moving from side to side in a wave-like motion, your finger will feel as if a raised dot is travelling up and down the comb. According to Hayward, this works because the unfamiliar motion of the teeth causes similar skin deformation to the more usual action of running your finger over a raised bump, so your brain interprets it that way. Another way to fool your fingertips is to cut up a Post-it note and glue parts of it to the back of a card as shown in the diagrams (right). Now close your eyes and run your fingertip along the thin central strips. You will probably feel a raised ridge or depressed trough, even though the surface of the reassembled Post-it notes is perfectly flush. This illusion relies on the fact that your finger slides more freely along the non-sticky area, causing skin deformations that are exactly like those when touching a ridge or trough. Your tongue is also very sensitive, and it can be fooled in a similar way. Take a fork and press the tip of your tongue between the prongs. You will feel as though the middle two prongs are bent out of shape. This is because the skin on your tongue is distorted in a way that doesn't normally happen, so your brain assumes that the prongs, not your tongue, are bent. © Copyright Reed Business Information Ltd

Keyword: Pain & Touch
Link ID: 12647 - Posted: 06.24.2010

By Laura Sanders Harry Potter had it easy: All he had to do to see another wizard’s memories was peer into that wizard’s swirling pensieve. Mind-reading is not so simple for everybody else. But a new study reveals that even those without magical gadgets may one day “see” someone else’s memories. In the study, which appears online March 12 in Current Biology, researchers used patterns of brain activity to accurately predict where someone was standing in a virtual room. Each of four study participants sat down to a computer and toured a large virtual room. The room contained objects that helped volunteers get oriented, including clocks, chairs and pictures. As participants navigated through the virtual space, brain cells preserved the memory of the route taken to the final location (“turn left at the picture of the boat”). Once participants reached their destinations, they stared at blank virtual floor for five seconds. Only then did the researchers measure brain activity with fMRI, to ensure that the measured brain activity stemmed from the memories of getting to the location and not from thoughts associated with any particular object in the virtual room. “Because the floor was identical at each target location, then the only thing we could have been decoding was the spatial location,” explains Eleanor Maguire of University College London, a coauthor of the study. © Society for Science & the Public 2000 - 2009

Keyword: Learning & Memory; Brain imaging
Link ID: 12646 - Posted: 06.24.2010

By Haley Stephenson The bad memories instilled by a car accident or other traumatic event are best forgotten. That might soon be possible, now that researchers have identified neurons in mice that store fearful memories and have found a way to wipe these memories clean. Fearful memories are housed within a region of the brain called the lateral amygdala (LA). When something scary happens, LA neurons produce higher levels of a protein called CREB (cyclic adenosine monophosphate response element-binding protein). Previous studies have erased fear memories by blocking enzyme action in this brain region (ScienceNOW, 23 October 2008), however this study took another approach. Scientists suspected the CREB-making neurons were doing the actual "remembering" of fear, acting as the key to removing fearful memories, so they decided to destroy them and see what happened. First, Sheena Josselyn, a neuroscientist at the University of Toronto in Canada and colleagues put mice through fear training. When a tone played, the mice received an electrical shock to their feet. After several rounds, the mice froze in fear at the sound. Then the team flipped a genetically engineered switch that killed CREB-making neurons. When the researchers played the tone again 2, 5, even 12 days later, the mice didn't freeze--they forgot their fear. No other memories seemed to be affected, the team reports tomorrow in Science. The mice could store new memories, such as how to find cheese in a maze, and even relearn the foot-shock fear response, but only with training. Even when researchers killed a random assortment of LA neurons, fear-memory formation remained intact. "By destroying specific neurons, instead of deleting an entire brain region, our findings show for the first time which neurons store a [fearful] memory," says neuroscientist and co-author Jin-Hee Han of the University of Toronto. © 2009 American Association for the Advancement of Science

Keyword: Learning & Memory; Emotions
Link ID: 12645 - Posted: 06.24.2010

By Tina Hesman Saey Plants do shift work too. Researchers have now discovered an important worker on the second shift. Jose Pruneda-Paz, Steve A. Kay and their colleagues at the University of California, San Diego report in the March 13 Science that they have found a missing link in plants’ circadian clocks. A regulatory protein called CHE connects a morning cycle to an evening cycle. Daily rhythms in plants, animals and microorganisms are governed by circadian clocks. Even though the clocks keep time in much the same way, the genes and proteins that make up the gears differ. Scientists are still uncovering all the gears of plants’ clocks. Plants have a large number of regulatory proteins, called transcription factors, which wind the clock and keep it running on time. These transcription factors are organized in multiple feedback loops that help make timing more precise, Kay says. People used to think of the circadian clock as a simple circle, but no more. “All of a sudden it’s turned into something that looks like the Olympic flag, multiple interlocking loops,” Kay says. Scientists previously discovered that the morning shift in plants is governed by a protein known as CCA1, and the night shift is under control of TOC1. But researchers didn’t know who punched the clock on the second shift. © Society for Science & the Public 2000 - 2009

Keyword: Biological Rhythms
Link ID: 12644 - Posted: 06.24.2010