Molecular basis of behavior
circadian rhythms, clock genes, light, photoreceptors, sleep.
Description of Research
The laboratory is interested in the molecular basis of behavior. The major emphasis, to date, has been on the mechanisms underlying circadian rhythms of rest:activity, using Drosophila as a model system. Our accomplishments in this area include the isolation of the timeless clock gene, the finding that timeless (tim) functions in an autoregulatory loop that lies at the core of the endogenous clock, elucidating the mechanisms that synchronize the clock to light and discovering mechanisms that transmit signals from the clock and produce overt rest:activity rhythms. In addition, we have investigated the role of clocks in peripheral (non-brain) tissues in Drosophila as well as mammals. We recently also initiated studies of other behaviors, such as sleep. We and our collaborators established Drosophila as a model system for sleep research. This genetic model for sleep allows us to address longstanding questions about sleep regulation and function that were previously difficult to tackle. Ongoing work in the laboratory is directed towards understanding the control of physiology and behavior by the clock, the genetic and molecular basis of sleep and, finally, the relationship of the circadian and sleep systems to other aspects of physiology, in particular to metabolism.
Rotation Projects for 2009-10
1. Identify neurons that regulate rhythmic feeding behavior
2. Investigate mechanisms underlying fragmentation of sleep with age
3. Characteize putative new molecular components of the circadian clock
2 Research Assistant Professors
10 postdoctoral fellows
3 graduate students
1 lab assistant
1 administrative assistant
Zheng, X., Koh, K., Sowcik, M., Smith, C.J., Chen, D., Wu, M.N. and Sehgal, A.: “An isoform-specific mutant reveals a role of PDP1ε in the circadian oscillator”. J. Neurosci. 29: 10920-10927, 2009.
Wu, M.N., Ho, K., Crocker, A., Yue, Z., Koh, K., and Sehgal, A.: “The Effects of Caffeine on Sleep in Drosophila Require PKA Activity, but not the Adenosine Receptor”. J. Neurosci. 29: 11029-11037, 2009.
Wu, Y., Bolduc, F.V. Bell, K.,Tully, T.,Fang, Y., Sehgal, A. and Fischer, J.A.: “A Drosophila Model for Angelman Syndrome”. Proc. Natl., Acad. Sci. USA 105: 12399-12404, 2008.
Xu, K., Zheng, X. and Sehgal, A.: "Regulation of feeding and metabolism by neuronal and peripheral clocks in Drosophila". Cell Metab. 8: 289-300, 2008 Notes: (Accompanied by a mini-review by Allada, R.).
Koh, K., Joiner, W.J., Wu, M.N., Yue, Z., Smith, C.J., and Sehgal, A: “Identification of SLEEPLESS, a novel sleep-promoting factor”. Science 321: 372-376, 2008 Notes: (Accompanied by a news story in Science and in several other journals).
Crocker, A. and Sehgal, A.: “Octopamine regulates sleep in Drosophila through protein kinase A-dependent mechanisms”. J. Neurosci. 28: 9377-9385, 2008.
Sathyanarayanan, S., Zheng, X., Chen, D., Hay, B. and Sehgal, A.: “Identification of novel genes involved in the circadian response to light through a genome-wide RNAi screen”. Genes & Dev. 11: 1522-1533, 2008.
Fang, Y., Sathyanarayanan, S. and Sehgal, A.: “Post-translational regulation of the Drosophila clock requires protein phosphatase 1". Genes & Dev 21: 1506-1518, 2007.
Koh, K., Zheng, X. and Sehgal, A.: “JET-LAG promotes light-induced degradation of the clock protein, timeless”. Science 312: 1809-1812, 2006.
Joiner, W.J., Crocker, A., White, B.H. and Sehgal, A.: “Sleep in Drosophila is regulated by adult mushroom bodies”. Nature 441: 757-760, 2006.
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Last updated: 02/27/2015
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