Role of diencephalon and hypothalamus for pre-mating isolation among goby fishes

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K06439
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 46030:Function of nervous system-related
• Research Institution: Toyama College (2022-2023); University of Toyama (2021)
• Principal Investigator: Kawaguchi Masahumi 富山短期大学, その他部局等, 准教授 (30513056)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 魚類モデル / 求愛行動 / 視索前域 / 視床下部 / 間脳

Outline of Final Research Achievements

To elucidate the neural basis for the regulation of pre-mating isolation in the freshwater goby, we identified structures in the preoptic area, hypothalamus, and diencephalon of adult goby fish based on the distribution patterns of transcription factors and brain factors based on our knowledge of tetrapods. The results revealed the presence of homologous structures in the fish brain to the hypothalamic paraventricular nucleus, A13 of the indeterminate zone, and three compartments of pretectum in mammals. As a basis for analyzing male courtship behavior, we searched for behaviors specific to males during courtship. We found that courtship males were significantly more likely to return to the female's side within 1.5 seconds after leaving the female's side. In addition, we found that females courted by males exhibit a characteristic external morphology in which pixels with luminance values greater than 110 occupy more than 30% of the body surface.

Free Research Field

神経解剖学, 行動生態学

Academic Significance and Societal Importance of the Research Achievements

近年、本能行動や精神疾患の神経基盤を解明する目的で魚類がモデル動物として選択される機会が増えている。しかし、魚類は系統が非常に多様なため、魚種間でも脳構造の相同性に関する議論が遅れており、魚類の脳構造に関する一般化された理解がなされていない。本研究では、ヨシノボリ成魚の視索前域・視床下部・間脳について転写因子と脳内因子の分布パターンを解析し、四足動物との相同構造を明らかにした。今回の知見は、ゼブラフィッシュやメダカなど一般的な魚類モデルと人間の脳構造を比較する上でも参考となるものであり、学術的意義と共に社会的意義を有する。