Elucidating the possible mechanism to cope with the insecticides in Kuruma prawn (Penaeus Japonicus)

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K19157
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 40:Forestry and forest products science, applied aquatic science, and related fields
• Research Institution: Fisheries Research and Education Agency
• Principal Investigator: Hano Takeshi 国立研究開発法人水産研究・教育機構, 水産技術研究所(廿日市), 主任研究員 (30621057)
• Co-Investigator(Kenkyū-buntansha): 伊藤 真奈 国立研究開発法人水産研究・教育機構, 水産技術研究所(廿日市), 主任研究員 (60735900) ; 大嶋 雄治 九州大学, 農学研究院, 学術研究員 (70176874)
• Project Period (FY): 2021-07-09 – 2024-03-31
• Keywords: クルマエビ / 殺虫剤 / 脱皮 / 薬物代謝 / 体内濃度

Outline of Final Research Achievements

The present study assessed the relationships between molting and survival in estuarine resident marine crustacean species, the kuruma prawn Penaeus japonicus. A 96-h laboratory bioassay included the exposure of the crustacean to graded concentrations of insecticide fipronil. The results showed that mortality was more frequent in molted specimens than those that were unmolted. Possible reason for this observation might be explained by the fact that internal insecticide concentrations in molted specimens were higher than those of unmolted ones but comparable with those of dead ones. In addition, enzyme genes associated with the insecticide metabolism showed a tendency to increase in fipronil-exposed shrimps. We further observed down-regulation of molting-related metabolites after insecticide exposure. Taken together, it is evident that not to molt is a pivotal choice to allow the organism to survive the exposure period and minimize the internal body concentrations of the insecticide.

Free Research Field

環境毒性学

Academic Significance and Societal Importance of the Research Achievements

クルマエビを含む甲殻類において「脱皮」は成長にとって重要なイベントである。これまで「脱皮」と殺虫剤影響との関係を詳細に調べた研究事例は皆無であった。本研究は、クルマエビが「脱皮をしない」選択をすることが殺虫剤曝露を生き抜く有効な戦略であることを示した。一方、クルマエビは成長のためには「脱皮」を繰り返す必要がある。人為的化学物質がクルマエビ稚エビの生存戦略を攪乱している可能性を示唆した点において本研究の意義は大きいと考える。