The mechanism of oocyte maturation in sea cucumber.

• Project/Area Number: 24570072
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Morphology/Structure
• Research Institution: Kyushu University
• Principal Investigator: YOSHIKUNI Michiyasu 九州大学, (連合)農学研究科(研究院), 教授 (50210662)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥5,590,000 (Direct Cost: ¥4,300,000、Indirect Cost: ¥1,290,000); Fiscal Year 2014: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000); Fiscal Year 2013: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000); Fiscal Year 2012: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• Keywords: 卵成熟 / 濾胞細胞 / 神経ホルモン / ニセクロナマコ / マナマコ / 排卵 / 卵黄タンパク質 / 卵黄蛋白質 / 卵黄形成 / 卵成熟誘起ホルモン / ホルモン / 生理活性物質 / 海洋資源 / 神経ペプチド

Outline of Final Research Achievements

The nerve tissue of sea cucumber contains a neuropeptide which stimulates ovarian follicle cells to secret a second hormone in inducing oocyte maturation and ovulation. The neuropeptide was purified from Holothuria leucospilota and identified its peptide sequence. The homologous peptides were also found in genomic data of Apostichopus japonicus and Holothuria scabra. These peptides may play as the common hormone in various sea cucumbers.
Coelomic fluid of Apostichopus japonicus contains a lot of small vesicles which are collected after ultracentrifugation. Analysis by SDS-polyacrylamide gel electrophoresis revealed that these vesicles contain the major yolk protein. These vesicles may be involved in the transport system of the yolk protein in sea cucumber.
The nerve tissue of Apostichopus japonicus may contain an activity which induces ovulation of fully grown oocytes without oocyte maturation.

Research Products

• [Journal Article] ハネジナマコの生殖腺と卵巣の周年変化 (2014)
  • Author(s): 南洋一、吉国通庸
  • Journal Title: 水産増殖 Volume: 未定
  • Peer Reviewed
• [Presentation] マナマコにおける卵黄蛋白質の輸送機構 (2014)
  • Author(s): Hoang Ding Chieu,吉国通庸
  • Organizer: 日本動物学会
  • Place of Presentation: 東北大学
• [Presentation] Comprehensive Analysis of Neuropeptides of Marine Invertebrates (2012)
  • Author(s): Michiyasu Yoshikuni
  • Organizer: 12th International Congress of the International Society for Developmental & Comparative Immunology
  • Place of Presentation: Fukuoka City
  • Invited
• [Presentation] 海産無脊椎動物の神経分泌ペプチドの網羅的解析 (2012)
  • Author(s): 吉国通庸
  • Organizer: 基礎生物学研究所研究会
  • Place of Presentation: 岡崎市
  • Invited
• [Presentation] Neural peptides induce oocyte maturation and gamete spawning of sea cucumber, Holothuria scabra. (2012)
  • Author(s): Yoichi Minami and Michiyasu Yoshikuni
  • Organizer: 10th Japan-Korea, Korea-Japan Joint Symposium on Aquaculture
  • Place of Presentation: Nagasaki City
• [Book] 科研費ＮＥＷＳ (2012)
  • Author(s): 吉国通庸
  • Total Pages: 23
  • Publisher: 文部科学省・日本学術振興会
• [Book] ナマコ学 -生物・産業・文化- 第3章 成熟・産卵 (2012)
  • Author(s): 吉国通庸
  • Total Pages: 227
  • Publisher: 成山堂
• [Remarks] 九州大学大学院農学研究院動物資源科学部門アクアフィールド科学分野吉国研究室
  • URL: http://www.agr.kyushu-u.ac.jp/lab/jikkensho/yoshikuni_lab/yoshikuni_top.html