Mechanisms underlying intracortical distribution of inhibitory interneurons and their synaptic connections

2015 Fiscal Year Final Research Report

• Project/Area Number: 22220004
• Research Category: Grant-in-Aid for Scientific Research (S)
• Allocation Type: Single-year Grants
• Research Field: Neuroscience in general
• Research Institution: Osaka University
• Principal Investigator: Murakami Fujio 大阪大学, 生命機能研究科, 名誉教授 (20089882)
• Co-Investigator(Kenkyū-buntansha): SONG Wen-Jie 熊本大学, 大学院生命科学研究部, 教授 (90216573) ; YAMAMOTO Nobuhiko 大阪大学, 大学院生命機能研究科, 教授 (00191429)
• Project Period (FY): 2010-04-01 – 2016-03-31
• Keywords: 大脳皮質 / 抑制性介在ニューロン / 移動の終了 / 皮質内最終分布 / 極性獲得

Outline of Final Research Achievements

The present study was performed to gain insight into the mechanisms of migration termination and final distribution of cortical interneurons (CIs) within the neocortex. To this end we developed a system in which migrating CIs can be observed in living embryos. We found that the CIs migrate in all directions in the marginal zone (MZ) and medially in the intermediate/subventricular zones. We also found that the termination of migration is regulated both by intrinsic and extrinsic mechanisms using time-lapse imaging of dissociated CIs and cortical explants. At the final settlement CIs extend axons and dendrites. We carried out time-lapse imaging for days and found the polarity of migrating CIs is not inherited by mature neurons but rather they acquire a new polarity de novo. There is a variety of subtypes of CIs and each of them shows intracortical distribution of its own. We found that random walk-like migration of CIs in the MZ is required for the final distribution of CIs subtypes.

Free Research Field

神経科学