We have isolated and analyzed DNA sequences encompassing the period (per) locus of Drosophila melanogaster. The location of this clock gene was delimited by the molecular mapping of chromosome aberrations at or very near the per locus. At least five RNAs are transcribed from this region. One of these transcripts, a 0.9 kb species, is strongly implicated in per's control of biological rhythms. Two independently isolated arrhythmic mutations at the per locus dramatically reduce the level of this transcript. Furthermore, the level of the 0.9 kb transcript is strongly modulated during a light/dark cycle. We discuss evidence, from previously reported genetic and phenotypic analysis of per's function, suggesting that this region may be complex and that several gene products from the per region, including this 0.9 kb transcript, may be involved in the different aspects of normal rhythmicity influenced by this clock gene.
This research output has an Altmetric Attention Score of 67. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 14 October 2025.
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Outputs of similar age from Cell
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Altmetric has tracked 33,031,246 research outputs across all sources so far. Compared to these this one has done particularly well and is in the 97th percentile: it's in the top 5% of all research outputs ever tracked by Altmetric.
So far Altmetric has tracked 19,226 research outputs from this source. They typically receive a lot more attention than average, with a mean Attention Score of 62.9. This one has done well, scoring higher than 81% of its peers.
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We're also able to compare this research output to 46 others from the same source and published within six weeks on either side of this one. This one has done particularly well, scoring higher than 97% of its contemporaries.
