New research on the fruit-fly brain points to a possible mechanism by which temperature influences the body clock, according to scientists from Queen Mary, University of London.
Although much is known about how light affects the body clock – also known at the circadian clock – it is not well understood which cells or organs sense daily temperature changes or how temperature signals reach the part of the brain that contains the circadian clock.
A variety of organisms, including insects and humans, have evolved an internal circadian clock to regulate patterns of behaviour throughout the day – for example sleep, appetite, alertness and concentration.
Senior study author Dr Ralf Stanewsky, from Queen Mary’s School of Biological and Chemical Sciences, explains: “Given the substantial similarity between the fly and mammalian clock, our studies might also help to understand the human circadian clock and in the future perhaps contribute to developing treatments against the negative effects of sleep-disorders and shift-work.”
Specially evolved “clock cells” in the brain contain the circadian clock, which needs to be synchronised with the natural environmental cycles every day to prevent them running too fast or too slow.
Dr Stanewsky and colleagues have shown that fly brains were unable to synchronize to temperature cycles when separated from the rest of the body. This is in contrast with the ability to synchronize to light-dark cycles, which can take place with or without a connection to the fly body.
This study, reported today in the journal Neuron, identified a gene called nocte that, when altered, interferes with the fly’s ability to synchronize its body clock using temperature signals. Importantly, disabling the nocte gene in nerve cells in the body also prevented the brain’s ability to synchronize with temperature.
Dr Stanewsky’s group wants to continue their studies on the fruit fly Drosophila and ultimately learn how the fly ensures perfect synchronisation of the circadian clock with the environment.
Notes to Editors
Queen Mary, University of London is one of the UK’s leading research-focused higher education institutions with some 15,000 undergraduate and postgraduate students.
Amongst the largest of the colleges of the University of London, Queen Mary’s 3,000 staff deliver world class degree programmes and research across 21 academic departments and institutes, within three sectors: Science and Engineering; Humanities, Social Sciences and Laws; and the School of Medicine and Dentistry.
Queen Mary is ranked 11th in the UK according to the Guardian analysis of the 2008 Research Assessment Exercise, and has been described as ‘the biggest star among the research-intensive institutions’ by the Times Higher Education.
The College has a strong international reputation, with around 20 per cent of students coming from over 100 countries.
Queen Mary has an annual turnover of £220 million, research income worth £61 million, and generates employment and output worth £600 million to the UK economy each year.
Queen Mary, as a member of the 1994 Group of research-focused universities, has made a strategic commitment to the highest quality of research, but also to the best possible educational, cultural and social experience for its students. The College is unique amongst London’s universities in being able to offer a completely integrated residential campus, with a 2,000-bed award-winning Student Village on its Mile End campus.