Our behavior adapts to the daily environmental cycle; generally we sleep at night and are alert during the day. These adjustments to external circadian cycles are the consequence of subtle molecular changes inside our body which are ultimately regulated and determined at the genetic level.
Researchers have known for some time that certain genes are turned on or off depending on the time of day. However, only some of the genes involved have been identified and they do not fully account for the mechanisms underlying perception and adaptation to daily cycles.
In the November 20 issue of Neuron, Young and colleagues report the identification of all these genes at once.
By using an array that allows them to monitor the state of activation of every gene in the head of a fruit fly at any given time, the research team has been able to establish which genes display daily cycles of expression.
Their results suggest that at least 160 genes (and possibly as many as 400) show cycling activation.
Initial analysis of these genes indicates that they code for proteins involved in diverse biological processes, such as learning and memory, sensory perception, locomotion and detoxification.
While some of these proteins were previously known to oscillate (thereby validating the technical approach of Young's team) the majority are novel. Hence, these experiments provide exciting new data to help understand how we perceive and adapt to daily cycles.
[Contact: Michael W. Young]
21-Nov-2001
