Developmental basis of extra-geniculate visual wathway

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K06756
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 48010:Anatomy-related
• Research Institution: Fukushima Medical University
• Principal Investigator: Watanabe Yuji 福島県立医科大学, 医学部, 講師 (80301042)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 発生 / 脳 / 神経 / 視覚 / 細胞移動 / 神経分化 / 回路形成 / 視蓋

Outline of Final Research Achievements

In humans, the extra-geniculate visual pathway from the retina transfers toward the associated visual cortex via superior colliculus and pulvinar to pursuit eye movement for tracking moving objects. In birds, this pathway carries both image recognition and visual movement, which is called tectofugal pathway via tectum and the nucleus rotundus. In this study, we demonstrated that the tangentially migrating cells in the developing chick optic tectum differentiate into SGC neurons in tectal layer 13, which have large dendritic fields and send an axon to the nucleus rotundus. Using recombinant vesicular stomatitis virus, we trans-synaptically labelled retino-tectal and tecto-rodundal projections constituting chick tectofugal visual pathway, and showed that SGC neurons comprise tectofugal visual pathway. These results suggest that tangential migration in early optic tectum is the key developmental process for arranging SGC neurons to form tectofugal visual pathway eventually.

Free Research Field

神経発生学

Academic Significance and Societal Importance of the Research Achievements

本研究で膝状体外系の視覚経路形成や進化に関する解剖発生学的な基盤を確立することにより、これを土台に特定の視覚経路での遺伝子操作や生理学的解析を組み合わせて、無意識の視覚のさらなる機能的解析が可能となる。