I was fantastically busy this past week, so I failed to alert you to new articles published in PLoS Computational Biology, PLoS Pathogens, PLoS Genetics and PLoS Neglected Tropical Diseases. I have posted my picks from the latter one. This week, my pick is this one, of course, as I have watched the previous microarray studies come out one by one, each identifying a different set of genes:
Meta-Analysis of Drosophila Circadian Microarray Studies Identifies a Novel Set of Rhythmically Expressed Genes:
Circadian genes regulate many of life’s most essential processes, from sleeping and eating to cellular metabolism, learning, and much more. Many of these genes exhibit cyclic transcript expression, a characteristic utilized by an ever-expanding corpus of microarray-based studies to discover additional circadian genes. While these attempts have identified hundreds of transcripts in a variety of organisms, they exhibit a striking lack of agreement, making it difficult to determine which, if any, are truly cycling. Here, we examine one group of these reports (those performed on the fruit fly–Drosophila melanogaster) to identify the sources of observed differences and present a means of analyzing the data that drastically reduces their impact. We demonstrate the fidelity of our method through its application to the original fruit fly microarray data, detecting more than 200 (133 novel) transcripts with a level of statistical fidelity better than that found in any of the original reports. Initial validation experiments (quantitative RT-PCR) suggest these to be truly cycling genes, one of which is now known to be a bona fide circadian gene (cwo). We report the discovery of 133 novel candidate circadian genes as well as the highly adaptable method used to identify them.