Location, location, location: important for jet-lagged circadian loops.

It is now believed that frequent jet lag or shifts of daily rhythms caused by rotating shift work can lead to deleterious health outcomes. Indeed, many serious health problems, including breast cancer, stroke, and cardiovascular disease, have been linked to an occupational history of shift work. This has heightened interest in better understanding the biological responses to jet lag and shift work, with the hope that this will pave the way to developing compounds that can help people avoid their negative health consequences. In this context, a report in this issue of the JCI takes us to a new level of understanding of the molecular control of the resetting of the multitude of internal biological clocks disrupted in a mouse model of jet lag.