Chemical Evolutionary Ecology Studies on the Repellent Substances from Shrews

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K21270
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 38:Agricultural chemistry and related fields
• Research Institution: Nagoya University
• Principal Investigator: KITA Masaki 名古屋大学, 生命農学研究科, 教授 (30335012)
• Co-Investigator(Kenkyū-buntansha): 森田 真布 名古屋大学, 附属菅島臨海実験所, 助教 (30865184) ; 大舘 智志 北海道大学, 低温科学研究所, 助教 (60292041)
• Project Period (FY): 2020-07-30 – 2022-03-31
• Keywords: 食虫動物 / トガリネズミ / 忌避物質 / 化学進化生態学

Outline of Final Research Achievements

Shrews are unique mammals that have poisons in saliva, and it has been suggested that their muscle tissue contain insect repellent substances, and the odor glands contain odorants that repel large mammals. In this study, we aimed to discover novel functional substances related to predation derived from shrews, and to understand their roles in evolution. The enzymatic activity of salivary gland extracts were evaluated, and we established the presence of several serine proteases related to blood coagulation, such as kallikrein, plasmin, and thrombin. In addition, the volatile components contained in the odor grands were analyzed by GC-MS or other methods, and a macrolactone known as a musk odor substance was identified. In the future, we will synthesize the identified compounds, confirm their activities, and elucidate their physiological functions.

Free Research Field

生物有機化学・ケミカルバイオロジー

Academic Significance and Societal Importance of the Research Achievements

様々な捕食動物のいる過酷な環境にて、小型の哺乳類であるトガリネズミ類はどのように生き延び、独自に進化してきたのか、進化生態学の観点からも大変興味深い。また微量・不安定物質の解析技術が進展した今、世界に先駆けて野生動物の極微量の生理活性物質に挑戦することは高い意義がある。生態学、進化生物学など関連諸分野とも連携して化合物の機能を解明し、長期的には生態系の理解や保全につながる研究への展開が期待される。また本研究の進展により化学合成品と比較しても環境負荷の少ない防虫剤や、鳥獣被害が深刻なイノシシ・熊避け剤など新規有用物質の創製が期待される点で、社会的意義も高い。