Biological Clock

Jobs with unsocial working hours should come with a serious health warning as nightshift workers face statistically higher risks of heart disease, diabetes, depression, and sleeping difficulties. Humans aren’t nocturnal and disruptions to our circadian rhythm, which regulates the cycle of sleep and wakefulness, can be debilitating. Anyone who’s experienced jetlag will confirm that our stubborn body clocks make us suffer when we try to shoehorn them into new time zones. It’s been known since the 1970s that a part of the brain called the suprachiasmatic nucleus (SCN) – bright spots middle bottom in this cross-section from a mouse – controls our sleep cycle. But what hasn’t been known until now is that the cycle could all be due to a single protein found in the SCN, called neuromedin, that brain cells use to communicate. The discovery gives scientists a new target to aim for when developing future treatments for sleep disorders.

Written by Tristan Farrow

Tristan Farrow

Writer

British Science Association Media Fellow. He holds a degree in quantum physics from the University of Cambridge and a Research Fellowship in quantum effects in biology.

• Image from work by Mariko Izumo and Martina Pejchal, and colleagues
• Departent of Neuroscience, University of Texas Southwestern Medical Center, Dallas, and Department of Neurobiology, Northwestern University, Evanston, USA
• Image originally published under a Creative Commons Licence (BY 4.0)
• Research published in Neuron, March 2015