Roles of spiral-like Ca2+ oscillationsin avian fertilization

2014 Fiscal Year Final Research Report

• Project/Area Number: 25660211
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Animal production science
• Research Institution: Shizuoka University
• Principal Investigator: SASANAMI Tomohiro 静岡大学, (連合)農学研究科(研究院), 准教授 (80322139)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: 受精 / 多精受精 / スパイラルカルシウムオシレーション / 精子ファクター / クエン酸合成酵素 / アコニット酸ヒドラターゼ / ウズラ

Outline of Final Research Achievements

Intracytoplasmic sperm injection (ICSI) has not been successful in birds because of the difficulty in mimicking the physiological polyspermy that takes place during normal fertilization. Here, we report that injection of a single spermatozoon with sperm extract (SE) or its components led to the development and birth of healthy quail chicks. SE contains three factors―phospholipase Cζ (PLCZ), aconitate hydratase (AH), and citrate synthase (CS)―all of which are essential for full egg activation and subsequent embryonic development. PLCZ induces a transient Ca2+ rise required for the resumption of meiosis. AH and CS are required for long-lasting, spiral-like Ca2+ oscillations, which are essential for cell cycle progression in early embryos. We also found that coinjection of cRNAs encoding 3 factors supported full development of ICSI-generated zygotes without the use of SE. These findings will help assist our understanding of the mechanism of avian fertilization and embryo developmen.

Free Research Field

繁殖生物学