Ability to form meiotic spindle is dependent on GV material

• Project/Area Number: 23657143
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Developmental biology
• Research Institution: Ochanomizu University
• Principal Investigator: CHIBA Kazuyoshi お茶の水女子大学, 大学院・人間文化創成科学研究科, 教授 (70222130)
• Project Period (FY): 2011 – 2012
• Project Status: Completed (Fiscal Year 2012)
• Budget Amount: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000); Fiscal Year 2012: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000); Fiscal Year 2011: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
• Keywords: 受精 / 減数分裂 / 卵母細胞 / ヒトデ / 星状体 / 多精 / 卵核胞 / 紡錘体 / 染色体 / 精子 / 卵 / 星状j体

Research Abstract

Before spawning, maternal asters existing near GV are affected by soluble components of GV other than chromosomes during GVBD, and acquire the ability to form functional spindles. Then, spawned oocytes are fertilized at MI. Although centrosomes of sperm form sperm asters, they wait to participate in cell cycle events until oocyte meiosis is completed: They cannot form functional spindles during meiotic division of oocytes, because GV components have been dispersed throughout the cytoplasm. When oocytes are isolated from the ovaries and artificially inseminated before GVBD or MI, polyspermy occurs and sperm asters at the animal pole are affected by GV components during GVBD and form abnormal multi-polar spindles interacting with maternal chromosomes during MI and MII. Thus, both spawning and fertilization at MI are important for maturing oocytes to be protected from formation of abnormal multi-polar spindles by paternal centrosomes.

Research Products

• [Journal Article] Sperm from sneaker male squids exhibit chemotactic swarming to CO_2 (2013)
  • Author(s): Hirohashi N, Alvarez L, Shiba K, Fujiwara E, Iwata Y, Mohri T, Inaba K, Chiba K, Ochi H, Supuran CT, Kotzur N, Kakiuchi Y, Kaupp UB, Baba SA
  • Journal Title: Current Biology Volume: 23 Issue: 9 Pages: 775-781
  • DOI: 10.1016/j.cub.2013.03.040
  • Peer Reviewed
• [Journal Article] Symmetrical division of mouse oocytes during meiotic maturation can lead to the development of twin embryos that amalgamate to form a chimeric hermaphrodite (2012)
  • Author(s): Otsuki, J., Nagai, Y., Lopata, A., Chiba, K., Yasmin, L., and Sankai, T
  • Journal Title: Hum. Reprod Volume: 27巻 Issue: 2 Pages: 80-387
  • DOI: 10.1093/humrep/der408
  • Peer Reviewed
• [Journal Article] Evolution of the acquisition offertilization competence and polyspermy blocks during meiotic maturation (2011)
  • Author(s): Chiba, K
  • Journal Title: Mol. Reprod. Dev Volume: 808-813 Issue: 10-11 Pages: 808-813
  • DOI: 10.1002/mrd.21378
  • Peer Reviewed
• [Journal Article] Arrest at metaphase of meiosis I in starfish oocytes in the ovary is maintained by high CO2 and low O2 concentrations in extracellular fluid Zool
  • Author(s): Moriwaki K, Nakagawa T, Nakaya F, Hirohashi N, Chiba K
  • Journal Title: Sci Volume: (印刷中)
  • Peer Reviewed
• [Presentation] Meiotic arrest and fertilization of starfish oocytes (2013)
  • Author(s): 千葉和義
  • Organizer: Oocyte maturation and fertilization meeting: Lessons from canonical and emerging models
  • Place of Presentation: in Banyuls-sur-Mer, France
  • Year and Date: 2013-06-13
• [Presentation] 卵減数分裂に干渉しない精子星状体 (2012)
  • Author(s): 長谷川翠、千葉和義
  • Organizer: 日本動物学会第83大会
  • Place of Presentation: 大阪大学
  • Year and Date: 2012-09-13
• [Presentation] ヒトデMI停止機構 (2012)
  • Author(s): 千葉和義
  • Organizer: 日本動物学会第83大会
  • Place of Presentation: 大阪大学
  • Year and Date: 2012-09-12
• [Presentation] ヒトデ卵MI停止機構 (2012)
  • Author(s): 千葉和義
  • Organizer: 日本動物学会第83大会
  • Place of Presentation: 大阪大学
• [Patent(Industrial Property Rights)] 反応方法および反応装置 (2012)
  • Inventor(s): 千葉和義
  • Industrial Property Rights Holder: 千葉和義
  • Industrial Property Number: 2012-016684
  • Filing Date: 2012-07-27
  • Overseas