Nearly every cell in your body contains a clock that tracks time of day. These circadian clocks program daily rhythms in behavior and physiology to ensure that biological processes occur at the right time of day. In mammals, the circadian system is a collection of biological clocks regulated by a master clock within the brain, known as the suprachiasmatic nucleus (SCN). As the master clock, the SCN controls clocks located throughout the brain and body so that they are optimally timed relative to one another and the external environment. Recent work indicates that disrupted clock function is linked to a wide variety of health disorders, including depression, learning deficits, cardiovascular disease, obesity, and cancer. Our laboratory investigates the functional organization of the circadian system in mammals, with the ultimate goal of gaining mechanistic insight that can be used to develop new therapeutic approaches for these health risks.
Towards this end, we focus on several key questions:
- How do SCN neurons communicate with one another?
- How does the SCN control other tissues of the body?
- How is the circadian system altered by changes in the environment (e.g., shiftwork, jetlag, seasons) and during disease states (e.g., addiction, neurodegeneration)?
- Are changes in clock function directly linked to pathology?
- What intrinsic and extrinsic factors increase the flexibility of the circadian system?
- Evans JA, Leise TL, Castanon-Cervates O, Davidson AJ. (2015). Neural correlates of individual differences in circadian behavior.Proc R. Biol Soc B,282: 20150769.
- Evans JA, Suen TC, Callif B, Mitchell A, Castanon-Cervates O, Baker KM, Kloehn I, Baba K, Teubner BJ, Bartness TJ, Ehlen JC, Paul KN, Tosini G, Leise TL, Davidson AJ (2015). Shell neurons of the master circadian clock coordinate tissue clocks throughout the brain and body.BMC Biology, 13(1), 43.
- Brancaccio M, Enoki R, Mazuski CN, Jones J, Evans JA, Azzi A. (2014). Network-mediated encoding of circadian time: The suprachiasmatic nucleus (SCN) from genes to neurons to circuits, and back.J Neuroscience,34(46):15192-9.
- Evans JA,Leise TL, Castanon-Cervantes O, & Davidson AJ. (2013). Dynamic interactions mediated by non-redundant signaling mechanisms couple circadian clock neurons. Neuron,80(4), 973-83.
- Evans JA & Davidson AJ. (2013). Health consequences of circadian disruption in humans and animal models. In ProgMoleBiolTransl Sci, 119, 283-323.
- Sellix M, Evans JA, Leise TL, Castanon-Cervantes O, Hill D, DeLisser P, Block GD, Menaker M, & Davidson AJ. (2012). Aging differentially affects re-entrainment responses of central and peripheral circadian oscillators. J Neuro, 32(46), 16193-16202.
- Evans JA, Pan H, Liu AC, & Welsh DK. (2012). Cry1-/- circadian rhythmicity depends on SCN intercellular coupling. J Biol Rhythms, 27(6), 443-452.
- Evans JA, Leise TL, Castanon-Cervantes O, & Davidson AJ. (2011). Intrinsic regulation of spatiotemporal organization within the suprachiasmatic nucleus. PLoS One, 6(1), e15869.
- Evans JA, Elliott JA, & Gorman MR. (2010). Dynamic interactions between coupled oscillators of the hamster circadian pacemaker. Beh Neuro, 124(1), 87-96.
- Evans JA, Elliott JA, & Gorman MR. (2009). Dim nighttime illumination accelerates adjustment to timezone travel in an animal model Curr Biol, 19(4), R156-157.