演題詳細
Symposium
光遺伝学や化学遺伝学を用いた神経回路機能操作と行動制御
Behavior control by manipulating neurocircuit using optogenetics and/or chemicogenetics
開催日 | 2014/9/12 |
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時間 | 17:10 - 19:10 |
会場 | Room B(501) |
Chairperson(s) | 成塚 裕美 / Hiromi Naritsuka (東京大学大学院 医学系研究科 細胞分子生理学教室 / Department of Physiology, Graduate School of Medicine, University of Tokyo, Japan) 山中 章弘 / Akihiro Yamanaka (名古屋大学環境医学研究所 / Research Institute of Environmental Medicine, Nagoya University, Japan) |
嗅球神経回路における成体新生顆粒細胞の活動依存的な組み込み様式の解析
Activity-dependent integration of adult-born granule cells into neuronal circuits of the mouse olfactory bulb
- S2-B-3-1
- 成塚 裕美 / Hiromi Naritsuka:1 森 憲作 / KENSAKU MORI:1 山口 正洋 / MASAHIRO YAMAGUCHI:1
- 1:東京大学・医・細胞分子生理 / Dept Physiol, Univ of Tokyo, Tokyo, Japan
The olfactory bulb (OB) is the first relay center in the mammalian olfactory system and its major local inhibitory interneurons, granule cells (GCs), are continually produced throughout adulthood. Adult-born GCs develop many dendritic spines which form reciprocal synaptic contacts with projection neurons. While olfactory sensory experience crucially regulates the spine development of adult-born GCs, it is not well known with which projection neurons among many projection neurons adult-born GCs make synaptic contacts and whether the choice of target projection neurons for adult-born GCs' synaptic contacts is regulated by the activity of the target projection neurons.
To address this question, we have established a mouse system in which channelrhodopsin was expressed in a subpopulation of mitral cells (MCs), the major projection neurons in the OB, and they are activated by photostimulation. Expression of channelrhodopsin-mCherry fusion protein revealed that both channelrhodopsin-expressing and non-expressing MCs were present in a given OB region. Dendritic spines of adult-born GCs were visualized by infecting with GFP-expressing virus. We are examining whether adult-born GCs make more synaptic contacts onto photoactivated MCs, compared with channelrhodopsin-negative MCs.
During the analysis of contact formation of adult-born GCs' dendritic spines onto MCs at various ages of adult-born GCs, we found that individual adult-born GCs form spines contacting somata of a limited number of MCs (perisomatic-targeting spines) from their early developmental stage. At the subsequent stage, adult-born GCs form well-studied spines that contact lateral dendrites of MCs (dendritic-targeting spines). We are examining whether formation of each of these subcellular-targeting spines is controlled by the activity of target MCs by the above optogenetic strategy.