在Ca的激活过程中
1Akkeshi Marine Biological Station, Faculty of Science, Hokkaido University, Akkeshi, Hokkaido 088-11, Japan.
Development, growth & differentiation
|June 7, 2023
概括
高pH触发了海精子体反应 (AR) 通过的流入,独立于蛋. 这一过程涉及一种由膜蛋白调节的特定运输系统.
科学领域:
- 海洋生物学 海洋生物学
- 精子生理学 精子生理学
- 细胞信号传输 细胞信号传输
背景情况:
- 体反应 (AR) 对于海的受精至关重要.
- 蛋通常通过增加细胞内 ([Ca2+]i) 和pH (pHi) 来触发AR.
- 在pH诱导的AR背后的特定机制尚未完全理解.
研究的目的:
- 为了研究高外部pH在诱导海精子中的体反应中的作用.
- 阐明涉及pH诱导AR的离子运输机制和调节蛋白.
- 为了比较pH诱导的AR的信号通路与蛋触发的信号通路.
主要方法:
- 对Hemicentrotus pulcherrimus的精子暴露在高pH (9.0) 的人造海水中.
- 使用光指示器测量细胞内 ([Ca2+]i) 和pH (pHi).
- 使用通道阻塞剂 (维拉帕米尔,尼索尔迪平) 和小麦芽聚合素 (WGA) 的抑制研究.
- 通过显微镜评估体反应 (AR).
主要成果:
- 高pH的海水诱导[Ca2+]i和pHi的显著增加,导致没有蛋的AR.
- [Ca2+]i的增加和pHi的增加取决于细胞外.
- 通道阻塞剂和WGA抑制了高pH和蛋诱导的AR.
- 通过N-乙-D-葡萄糖胺,WGA抑制是可逆的,这表明与特定的精子膜糖蛋白相互作用.
结论:
- 高的外部pH值激活了一个类似于蛋触发的运输系统.
- 增加的[Ca2+]i是刺激质子 (H+) 流出系统的先决条件.
- 一种220kD的WGA结合膜蛋白作为精子运输系统的调节者.
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