The sixth sense of snakes: How was their infrared reception acquired?

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K22461
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 45:Biology at organismal to population levels and anthropology, and related fields
• Research Institution: Toho University
• Principal Investigator: TOKITA Masayoshi 東邦大学, 理学部, 准教授 (80422921)
• Project Period (FY): 2019-06-28 – 2022-03-31
• Keywords: ヘビ / 赤外線受容 / ピット器官 / 発生 / 進化

Outline of Final Research Achievements

In this study, we aimed to describe the development of infrared receptive neural circuit of the snakes belonging to the subfamily Crotalinae through examination of the expression pattern of the gene encoding the temperature-sensitive channel TRPA1 in the embryonic head of the Japanese Mamushi (Gloydius blomhoffii) by in situ hybridization. The analysis confirmed that the TRPA1 gene is expressed in the infrared-sensitive neurons that comprise the infrared receptive neural circuit of the pit viper embryos. However, the amount of its expression was extremely low, making it difficult to obtain accurate staining data by in situ hybridization. Since reliable staining data that can be reported in a paper have not been obtained at this point, improvements of experiments are required in the future.

Free Research Field

脊椎動物比較形態学

Academic Significance and Societal Importance of the Research Achievements

生物の成長過程、つまり“個体発生”で見られる神経回路再編成についてはすでに多くの知見が得られているが、“系統発生”の視点から神経回路再編成の動態とそのメカニズムを探求した研究はほとんどなく、この点で本研究の挑戦的研究としての学術的意義は高いと言える。本研究を通して、神経回路再編成と生物進化との関連性を探究する進化生物学の新たな研究領域を開拓する土台も作ることができた。また、本研究を通じて赤外線受容神経回路の創出機構の一端が明らかにされたことで、医療・工業分野で利用される高精度温度センサーデバイスの開発にも少なからず貢献できる可能性がある。