Circadian clocks allow organisms to predict environmental changes caused by the rotation of the Earth. Although circadian rhythms are widespread among different taxa, the core components of circadian oscillators are not conserved and differ between bacteria, plants, animals and fungi. Stramenopiles are a large group of organisms in which circadian rhythms have been only poorly characterized and no clock components have been identified. We have investigated cell division and molecular rhythms in
Organisms track time of day through the function of cell-autonomous molecular clocks. In addition to a central clock located in the brain, molecular clocks are present in most peripheral tissues. Circadian clocks are coordinated within and across tissues, but the manner through which this coordination is achieved is not well understood. We reasoned that the ability to track in vivo molecular clock activity in specific tissues of the fruit fly, Drosophila melanogaster, would facilitate an investigation into the relationship between different clock-containing tissues. Previous efforts to monitor clock gene expression in single flies in vivo have used regulatory elements of several different clock genes to dictate expression of a luciferase reporter enzyme, the activity of which can be monitored using a luminometer. Although these reporter lines have been instrumental in our understanding of the circadian system, they generally lack cell specificity, making it difficult to compare molecular clock oscillations between different tissues. Here, we report the generation of several novel lines of flies that allow for inducible expression of a luciferase reporter construct for clock gene transcriptional activity. We find that these lines faithfully report circadian transcription, as they exhibit rhythmic luciferase activity that is dependent on a functional molecular clock. Furthermore, we take advantage of our reporter lines’ tissue specificity to demonstrate that peripheral molecular clocks are able to retain rhythmicity for multiple days under constant environmental conditions.
more » « less- Award ID(s):
- 1942167
- NSF-PAR ID:
- 10384893
- Publisher / Repository:
- SAGE Publications
- Date Published:
- Journal Name:
- Journal of Biological Rhythms
- Volume:
- 38
- Issue:
- 1
- ISSN:
- 0748-7304
- Page Range / eLocation ID:
- p. 44-63
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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C. floridanus , thus, likely represent a more general phenomenon that warrants further investigation.
