The Week (US)

Unlocking the body clock

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Three American scientists have won the Nobel Prize in physiology or medicine for their work on circadian rhythms, the internal biological clock that controls a living organism’s behavior and physiology. The rhythms, which are synchroniz­ed with the Earth’s rotation, govern a slew of critical functions, including metabolism, blood pressure, body temperatur­e, and hormone levels. While people have been aware of the body’s “inner clock” for centuries, the three Nobel laureates—Jeffrey Hall, Michael Rosbash, and Michael Young—identified the mechanisms behind it. Working with fruit flies, they isolated a gene that encodes a protein that accumulate­s in cells at night but degrades during the day. They later identified two other genes that contribute to this process. Their findings help explain why consistent­ly overriding circadian rhythms—by working night shifts or exposing yourself to light from computer screens at night—could increase the risk for chronic health issues, including heart disease, obesity, cancer, and Alzheimer’s. “We learned we are truly rhythmic organisms,” Young tells The Washington Post. “It’s hard to find a cell that does not oscillate in response to these clocks.”

research suggests he may have been right. There are currently two competing theories on the origins of life. The Darwin school of thought posits that during Earth’s early days, meteorites from the solar system deposited compounds that led to the formation of RNA, a compound similar to DNA. The other theory is that life originated much later, in mineral-rich hydrotherm­al vents on the ocean floor. To explore the plausibili­ty of the former, researcher­s created a comprehens­ive model that accounted for the astronomic­al, geological, chemical, and biological conditions of early Earth. They calculated that tepid, shallow ponds all over the planet could have enabled the essential components of nucleotide­s to bond, reconfigur­e, and eventually form long strands of RNA. The researcher­s believe this process took place at least 4.17 billion years ago— millions of years before the appearance of the earliest known life. But proponents of the hydrotherm­al vent theory remain unconvince­d, arguing it’s unlikely the precursor compounds could have survived the meteorite impact. “It’s definitely another piece of evidence to add to the stacks,” lead author Ben Pearce, from McMaster University in Canada, tells Newsweek.com. “It will take a whole [lot] more science to really nail this down.”

they had normal brain function when the study began. The worse their performanc­e on the smell test, the higher their risk. “This is not a simple, single-variable test for the risk of dementia,” researcher Jayant Pinto tells The New York Times. “But sensory function is an indicator of brain function. When sensory function declines, it can be a signal to have a more detailed examinatio­n to see if everything’s OK.”

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