That these clocks exist is well established, but discerning how they work is another matter entirely. Clock researchers have found that the most fertile ground in which to study circadian rhythms is the fruit fly, Drosophila melanogaster. The step-by-step discovery of Drosophila clock genes, driven largely by screening mutant flies, has pushed forward the identification of corresponding mammalian clock genes.
Most researchers believe that the basic clock mechanism has now been elucidated, but little is known about how the clock communicates with the rest of the organism to control behavior. The availability of the complete sequence of the fly genome and tools for genome-wide expression has increased the understanding of how such communication is regulated. One such tool is the DNA microarray.
The first two studies that applied DNA microarray technology to circadian gene expression in Drosophila were published in October and November 2001. Michael McDonald and Michael Rosbash at ...
