Studies on tetrodotoxin origin in toxic flatworm: exploration of chemical cue for larval settlement and metamorphosis

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K15606
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 40040:Aquatic life science-related
• Research Institution: Nihon University
• Principal Investigator: SUO Rei 日本大学, 生物資源科学部, 助教 (20846050)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: テトロドトキシン / フグ毒 / 着底・変態 / ヒラムシ / 共生微生物

Outline of Final Research Achievements

Marine polyclad toxic flatworms constantly contain high concentrations of TTX, and are thought to be one of the animals responsible for the presence of TTX in some marine organisms. The larval development during the planktonic phase and the transition to the benthic juvenile of toxic flatworms has not been well-studied yet. The aim of this project was to identify chemical factors that may have effects on larval settlement and metamorphosis of the flatworm in order to establish an artificial rearing method for the flatworm larvae. We provided insight into the growth of flatworm larvae. In addition, TTX and several analogues such as 5,6,11-trideoxyTTX, monodeoxyTTXs, dideoxyTTXs, and 11-norTTX-6(S)-ol were identified from toxic flatworm extracts using high-resolution liquid chromatography-mass spectrometry.

Free Research Field

海洋天然物化学

Academic Significance and Societal Importance of the Research Achievements

フグ毒テトロドトキシン（TTX）は最も強力な自然毒の1つであり、数多くの海洋生物に含まれている。食料資源の安全性担保のためには、生態系におけるTTXの起源を明らかにする必要がある。本研究では高濃度のTTXを保有するヒラムシに焦点を当て、TTX関連化合物の保有状況、ならびに発生初期の生活史に関する知見を深めることができた。本研究成果は、海洋生物におけるTTXの起源解明の一助となることが期待される。