Functional analysis of ascidian larval nervous system with optogenetics and a single cell photo stimulation device

• Project/Area Number: 26650122
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Animal physiology/Animal behavior
• Research Institution: University of Hyogo
• Principal Investigator: Nakagawa Masashi 兵庫県立大学, 生命理学研究科, 助教 (00212085)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2016: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2015: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2014: ¥2,860,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥660,000)
• Keywords: 神経回路 / 光遺伝学 / ホヤ幼生 / 神経機能 / 行動

Outline of Final Research Achievements

The origin of vertebrate brain is thought to be that of the ascidian (sea squirt). Indeed, the larval central nervous system is derived from the neural tube. The nervous system is composed of only about 200 neurons. Previously, we found that a simple neural circuit which is composed with 2 cholinergic neurons and 2 GABA/glycinergic neurons. We deduced that the simple circuit gave rise to tail beating behavior. We produced a novel single cell photo-stimulation device, which can excite a single target cell. We excited a single GABA/glycinergic neuron for a while. After the excitation light was off, the larval tail beating started. The result suggested that this simple neural circuit is a central patter generator of tail beating.