Michael Hastings

Molecular neurobiology of circadian timing

Maywood ES, Chesham JE, O'Brien JA, Hastings MH (2011)
A diversity of paracrine signals sustains molecular circadian cycling in suprachiasmatic nucleus circuits.
Proc Natl Acad Sci U S A. [Epub ahead of print] PMID: 21788520

Meng QJ, Maywood ES, Bechtold DA, Lu WQ, Li J, Gibbs JE, Dupré SM, Chesham JE, Rajamohan F, Knafels J, Sneed B, Zawadzke LE, Ohren JF, Walton KM, Wager TT, Hastings MH, Loudon AS. (2010)
Entrainment of disrupted circadian behavior through inhibition of casein kinase 1 (CK1) enzymes.
Proc Natl Acad Sci U S A.24;107(34):15240-5.

Deery MJ, Maywood ES, Chesham JE, Sladek M, Karp NA, Green EW, Charles PD, Reddy AB, Kyriacou CP, Lilley KS, Hastings MH. (2009)
Proteomic analysis reveals the role of synaptic vesicle cycling in sustaining the suprachiasmatic circadian clock.
Current Biology 19:2031- 2036.

Visit my group page here

Contact me by email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Group Members

Liz Maywood
Johanna (Jo) Chesham
Nick McGlincy
Marco Brancaccio
Nicola Smyllie
Mathew Edwards

Circadian rhythms are those daily cycles of physiology and behaviour that persist when organisms are isolated from the external world. They are expressed at all levels of life, from prokaryotic blue-green algae to higher plants and animals. Their biological role is to anticipate and thereby allow organisms to adapt to the solar day and night. In humans the cycle of sleep and wakefulness is the most obvious circadian rhythm, reflecting a profound alternation of brain states. Disruption of our circadian programme through shift work, old age and neurological disease is a significant and growing cause of chronic illness.

The principal circadian pacemaker is located in the suprachiasmatic nucleus of the hypothalamus (SCN), where individual neurons can operate as selfsustained circadian clocks. This same clock mechanism is also present in our major organ systems; heart, lungs, liver, kidney etc. The SCN maintains synchrony amongst these sub-ordinate clocks via its control over behaviour, neuroendocrine pathways and the autonomic nervous system. The genes responsible for encoding our circadian clockwork have recently been identified.

We are using real-time in-vivo fluorescence and bioluminescence imaging, DNAmicroarrays, proteomic expression analyses and molecular genetic manipulations to understand how these "clock" genes and their protein products are able to assemble themselves into a 24h time-keeper, and how the central and peripheral timers together co-ordinate our metabolic and physiological rhythms. Through this approach we aim to provide a molecular genetic explanation for one of the most conserved and ancient forms of behaviour-circadian timing.

MRC Laboratory of Molecular Biology