Neuronal network level understanding of master circadian clock in mammals

2015 Fiscal Year Final Research Report

• Project/Area Number: 25860175
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Environmental physiology(including physical medicine and nutritional physiology)
• Research Institution: Hokkaido University
• Principal Investigator: Enoki Ryosuke 北海道大学, 医学(系)研究科(研究院), 助教 (00528341)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 概日リズム / 生物時計 / カルシウム / 光イメージング / 時計遺伝子 / 神経ネットワーク

Outline of Final Research Achievements

Circadian clocks in mammals are controlled by neuronal network activities in the suprachiasmatic nucleus (SCN) of the hypothalamus in the brain. The SCN controls 24h rhythms in physiology and behavior, such as sleep-wake cycles, hormone release, etc. However, the network-level mechanisms of circadian rhythm are poorly understood.
In the present study, we performed large-scale time-lapse imaging in large population of neurons in the SCN. I combined the methods of fluorescence imaging of intracellular calcium ion, bioluminescence imaging of clock gene expression, multi-electrode array dish for detecting neuronal firings, or voltage-sensitive fluorescent probes, and I succeeded, for the first time, in simultaneous recording of multiple neuronal functions (Calcium, gene expression, neuronal firing, etc) from identical locations in same SCN. I analyzed spatial patterns and temporal order of these functions, and found the functional link between these rhythms.

Free Research Field

神経生理学