演題詳細
Special Lectures
開催日 | 2014/9/11 |
---|---|
時間 | 14:00 - 15:00 |
会場 | Room A(Main Hall) |
Chairperson(s) | 岡本 仁 / Hitoshi Okamoto (理化学研究所 脳科学総合研究センター / RIKEN Brain Science Institute) |
脳神経系を解析するための学際的技術開発
Genetically encoded tools for brain analysis
- SL-1
- 宮脇 敦史 / Atsushi Miyawaki:1
- 1:理化学研究所BSI細胞機能探索技術開発チームRAP生命光学技術研究チーム / Laboratory for Cell Function Dynamics, RIKEN BSI, Biotechnological Optics Research Team, RIKEN RAP
The striking progress in genome science and gene technology has led to numerous discoveries and the rapid development of new technologies in the life sciences. These new technologies include "optogenetics" - a growing suite of techniques that combine optical and molecular genetic methods. The technologies employ genetically encoded tools and are becoming popular particularly in neuroscience, where the central challenge is to understand the mechanisms by which neurons process and integrate synaptic inputs and how these mechanisms are modified by activity.
Since the isolation of the GFP from the bioluminescent jellyfish in 1992 and the subsequent development of related molecules, genetically encoded sensors that enable fluorescence imaging of excitable cell activity have been constructed by fusing fluorescent proteins to functional proteins that are involved in physiological signaling. Because these sensors can be introduced by gene transfer techniques, they may extract neuronal signals from an intact brain more efficiently than conventional organic dyes. Also, their expression is driven in a certain population of neurons by the use of a specific promoter; this has made visualization of the connectivity between two or more different (sub)populations of neurons all the more exciting.
On the one hand, many genetically encoded sensors have been developed to investigate the function of specific signaling mechanisms in synaptic transmission, integration, and plasticity. The sensors that monitor signals resulting from electrical activity, such as free-Ca2+ concentration and pH, instead of transmembrane voltage, function as low-pass filters. On the other hand, optogenetic control of neuronal activity allows us to selectively activate or inactivate genetically defined populations of neurons in order to examine how the activity of these neurons contributes to the function of neural circuits in the brain.
Newly emerging genetically encoded tools will surely stimulate the imagination of many neuroscientists, and this is expected to spark an upsurge in the demand for them. As a result, fluorescence microscopes will inevitably be equipped with special hardware and software functions to optimize their use. In this regard, a significant evolution in microscopy will be necessary if optogenetic technologies are to enjoy widespread use.