PerspectiveNeuroscience

A CRY to Rise

+ See all authors and affiliations

Science  18 Mar 2011:
Vol. 331, Issue 6023, pp. 1394-1395
DOI: 10.1126/science.1204293

You are currently viewing the summary.

View Full Text

Summary

When we need to wake at a certain time, some of us resort to setting several alarm clocks to ring at different times, or in different locations, to ensure that we don't oversleep. The biological timing system appears to use a similar strategy: It relies on a multi-tiered approach to detect environmental signals and deliver multifaceted information regarding ambient light conditions. In Drosophila, a light-sensitive protein called CRYPTOCHROME (CRY) serves as a light sensor that each day helps to reset the fly's circadian clock. On page 1409 of this issue, Fogle et al. (1) show that CRY also directly increases the firing rate of critical circadian “pacemaker” neurons by sensing blue wavelengths of light. This represents a mechanism for photo-activation of neurons that is not based on opsin, the protein typically involved in light-responsive brain activity.