Clock

NYU researchers simulate molecular biological clock

For many years, DNA and proteins have beenviewed as the real movers and shakers in genomic studies, with RNA seenas little more than a messenger that shuttles information between thetwo. But researchers from Whitehead Institute for Biomedical Researchand Massachusetts Institute of Technology have discovered that smallRNA molecules called microRNAs regulate thousands of human genes--morethan...

Effective Cancer Treatments Follow The Clock

Oncologists have long thought that cancer treatments tend to be more effective at certain times of day. But they have been unable to turn this knowledge into practice, because they did not understand the phenomenon well enough. Now, researchers have discov...

Glow-in-the-dark zebrafish at UH hold keys to biological clocks

Using genetically altered zebrafish that glow in the dark, University of Houston researchers have found new tools that shed light upon biological clock cycles. Gregory M. Cahill, associate professor of biology and biochemistry at UH, and Maki Kaneko, a fellow UH researcher who is now at the University of California-San Diego, presented their findings in a paper titled "Light-dependent Dev...

After a time-shift, mixed signals from the circadian clock

Circadian rhythms in mammalian behavior, physiology, and biochemistry are controlled by the central clock within a brain structure known as the suprachiasmatic nucleus (SCN). The clock is synchronized to environmental cycles of light and dark. It is well known, from everyday experience, that adjusting to new light schedules takes several days, though the details of how this adaptation takes place...

The circadian clock: Understanding nature's timepiece

A cluster of brain cells less than half the size of a pencil eraser tells you when to wake up, when to be hungry and when it's time to go to sleep. The same cells also cause you to be disoriented after you've flown across multiple time zones. The human circadian clock, comprised of about 20,000 time-keeping cells, has mystified scientists since it was pinpointed in the brain about 30 year...

Discovery clarifies role of peptide in biological clock

A biologist at Washington University in St. Louis is giving the VIP treatment to laboratory mice in hopes of unraveling more clues about our biological clock. Erik Herzog, Ph.D., Washington Un...

Temperature regulates circadian clock in zebrafish

The biological clock controls the circadian rhythms of a wide range of physiological and behavioral processes, from fluctuating hormone levels to sleep-wake cycles and feeding patterns. While it's well known that circadian clock elements sense and respond to light cycles, much less is known about how daily temperature cycles affect the clock's timing mechanism in vertebrates. In the open-access...

What Makes The Brain Tick, Tick, Tick: Researchers Gaining New Insights Into Brain's Internal Clock

The brain is a "time machine," assert Duke neuroscientists Catalin Buhusi and Warren Meck. And understanding how the brain tracks time is essential to understanding all its functions. The brain's internal clocks coordinate a vast array of activities from communicating, to orchestrating movement, to getting food, they said. In a review article in the October 2005 Nature Reviews Neuroscience...

Clocking in Pillow Time without the Pillow

If you snooze, you lose those uncomely grayish-brown crescents below your eyes. If you don't snooze, you lose a lot more. The body can't fight off infection, the muscles can't regenerate as quickly, the mind can't learn new words, and the eyes can't focus on the road. You also gain things: a bad mood and increased risk for diabetes, high blood pressure, and heart problems. Indeed, the effects of...

Travelers can avoid jet lag by resetting their body clocks

A simple, at-home treatment -- a single light box and the over-the-counter drug melatonin -- allows travelers to avoid jet lag by resetting their circadian body clock before crossing several time zones, according to new research being published in The Endocrine Society's Journal of Clinical Endocrinology and Metabolism. This treatment can also help those with delayed sleep phase syndrome (DSPS),...

Clock molecule's sensitivity to lithium sheds light on bipolar disorder

Researchers at the University of Pennsylvania School of Medicine discovered that a key receptor protein is a critical component of the internal molecular clock in mammals. What's more, this molecule –called Rev-erb?is sensitive to lithium and may help shed light on circadian rhythm disorders, including bipolar disorder. The findings, which also provide insight into clock-controlled aspects of met...

More evidence mammals, fruit flies share make-up on function of biological clocks

A study by researchers at New York University and the University of London offers additional evidence that mammals and fruit flies share a common genetic makeup that determines the function of their internal biological clocks. The research team consisted of post-doctoral researcher Ben Collins, Esteban Mazzoni, a graduate student, and Assistant Professor Justin Blau of NYU's Department of...

Novel connection found between biological clock and cancer

Dartmouth Medical School geneticists have discovered that DNA damage resets the cellular circadian clock, suggesting links among circadian timing, the cycle of cell division, and the propensity for cancer. Their work, reported June 29 in Science Express, the advance electronic publication of Science, implies a protective dimension for the biological clock in addition to its pacemaker funct...

Internal body clock dictates timing of different types of stroke

The internal body clock, or circadian rhythm, seems to influence the timing of different types of stroke, suggests research published ahead of print in the Journal of Neurology Neurosurgery and Psychiatry. These patients' data had been...

A surprise about our body clock

Researchers at the McEwen Centre for Regenerative Medicine at Toronto General Hospital have discovered the 'SOS' distress signal that mobilizes specific heart repair cells from the bone marrow to the injured heart after a heart attack. While it has long been known that bone marrow cells have the ability to clear the dead tissue after a heart attack, what has not been known until now is the...

How nature tinkers with the cellular clock

The life of a cell is all about growing and dividing at the right time. That is why the cell cycle is one of the most tightly regulated cellular processes. A control system with several layers adjusts when key components of the cell cycle machinery are produced, activated and degraded to make sure that the schedule is kept. These layers of control work differently and are usually studied separate...

Protein shown to rally biological clock

A biologist at Washington University in St. Louis and his collaborators have identified the factor in mammalian brain cells that keeps cells in synchrony so that functions like the wake-sleep cycle, hormone secretion and loco motor behaviors are coordinated daily over a 24-hour period. Erik Herzog, Ph.D., Washington University associate professor of Biology in Arts & Sciences, Sara Ato...

Keeping the body in sync -- The stability of cellular clocks

A study in Switzerland uses the tools of physics to show how our circadian clocks manage to keep accurate time in the noisy cellular environment. In an article appearing March 13 in the journal Molecular Systems Biology, researchers from the Ecole Polytechnique Federale de Lausanne demonstrate that the stability of cellular oscillators depends on specific biochemical processes, reflecting...

Individual differences in a clock gene predict decline of performance during sleep deprivation

People are known to differ markedly in their response to sleep deprivation, but the biological underpinnings of these differences have remained difficult to identify. Researchers have now found that a genetic difference in a so-called clock gene, PERIOD3, makes some people particularly sensitive to the effects of sleep deprivation. The findings, reported by Antoine Viola, Derk-Jan Dijk, and colle...