Age-related changes in ovarian gene expression in Pacific bluefin tuna

• Project/Area Number: 25450294
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Aquatic bioproduction science
• Research Institution: Japan Fisheries Research and Education Agency
• Principal Investigator: GEN KOICHIRO 国立研究開発法人水産総合研究センター, その他部局等, 研究員 (80372051)
• Co-Investigator(Kenkyū-buntansha): KAZETO Yukinori 水産総合研究センター, 増養殖研究所, 主任研究員 (60399996) ; MEKUCHI Miyuki 水産総合研究センター, 中央水産研究所, 研究員 (40594007)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000); Fiscal Year 2015: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2014: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2013: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• Keywords: クロマグロ / 初回成熟 / 成熟誘導遺伝子 / 卵巣 / 繁殖生理 / 水産増養殖

Outline of Final Research Achievements

An understanding of the mechanism underlying puberty is important for establishment of tuna farming. In this study, we aim to characterize reproductive-related genes in Pacific bluefin tuna and to examine changes in their expression levels during the pubertal to adulthood period in ovary. Using standard cloning technique, we have obtained 50 candidate genes for reproductive traits in bluefin tuna ovary. Comparative analysis of gene expression revealed that transcripts encoding steroid hormone synthase and receptors (PR, AR) of pubertal female were significantly higher than that of adult female. In contrast, adult fish showed significantly higher levels of ovary ARID and CREB mRNA and circulating estrogens. These results suggested that age-related changes in reproductive-related genes expression may result from alterations in ovarian development characteristics and serum estrogens in pubertal female.

Research Products

• [Presentation] 養殖クロマグロの加齢に伴う繁殖特性の変化 (2015)
  • Author(s): 玄浩一郎、馬久地みゆき、風藤行紀、二階堂英城
  • Organizer: 平成２７年度日本水産学会春季大会
  • Place of Presentation: 東京海洋大学（品川キャンパス）
  • Year and Date: 2015-03-30
• [Presentation] Evaluation of seasonal variation in reproduction-related gene expression in the pacific bluefin tuna Thunnus orientalis using nest-generation sequencing
  • Author(s): Mekuchi, M., Yasuike, M., Ojima, N., Gen, K., Sugaya, T., Nikaido, H., Shimizu, S.
  • Organizer: International Plant and Animal Genomics
  • Place of Presentation: San Diego, CA, USA
• [Book] Biology and Ecology of Bluefin Tuna (2015)
  • Author(s): Gen K.
  • Total Pages: 30
  • Publisher: CRC Press
• [Book] マグロの資源と生物学 (2014)
  • Author(s): 松原孝博、玄浩一郎、澤口小有美、持田和彦、二階堂英城
  • Total Pages: 13
  • Publisher: 成山堂