Mechanisms regulating spatial patterning of dendrites by environmental sensing

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K18363
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Neurophysiology / General neuroscience
• Research Institution: Kyoto University
• Principal Investigator: Fujishima Kazuto 京都大学, 高等研究院, 特定助教 (20525852)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 神経回路 / プルキンエ細胞 / フィロポディア / アクチン骨格 / 樹状突起 / 形態形成

Outline of Final Research Achievements

Cerebellar Purkinje cells construct their characteristic dendrites during development. Their dendritic filopodia sense the environmental cues and modify their growth dynamics to attain their appropriate shapes. We attempted to clarify the mechanisms controlling the dynamics from two points of view.　(1) The dendrites recognize the contact between dendritic arbors and eliminate the arbor to avoid excess crossing. We found that actin-regulator Mtss1 regulates the filopodial length and modify the frequency of contact between dendritic branches. We further demonstrated the mechanisms of how Mtss1 control the actin polymerization to modify filopodial length.　(2) The dendrites recognize the parallel fiber to control their dendrite growth orientation. The dendrites grow perpendicular to parallel fibers. We performed time-lapse imaging of dendrite growth during perpendicular growth to understand the mechanisms and attempted to identify the molecule to be involved in the recognition.

Free Research Field

神経発生

Academic Significance and Societal Importance of the Research Achievements

本研究では小脳プルキンエ細胞をモデルとし、ニューロンが発生期において組織内環境を認識しながら適切な形態を獲得する仕組みの解析を行った。樹状突起が固有の空間配置を獲得する上で、フィロポディアによる環境認識が一定の役割を果たすことを示した。本研究によって得られた知見は、哺乳類の神経回路形成メカニズムを理解する上で重要なものであり、将来的には発生不全に伴う神経疾患などの発症メカニズムへ貢献する可能性がある。