在海蛋中,NAADP从储备颗粒,溶酶体相关有机体中调动Ca2+)
Grant C Churchill1, Yuhei Okada, Justyn M Thomas
1Department of Pharmacology, University of Oxford, Mansfield Road, OX1 3QT, Oxford, United Kingdom. grant.churchill@pharm.ox.ac.uk
Cell
|December 5, 2002
概括
尼古丁酸腺因二核酸 (NAADP) 从海蛋中的新型酸性储物 - - 储备颗粒中释放. 这个过程依赖于质子,揭示了一个新的信号通路.
科学领域:
- 细胞生物学 细胞生物学
- 信号传递的.
- 分子生理学分子生理学
背景情况:
- 尼古丁酸腺因二核酸 (NAADP) 是一种强大的 (Ca2+) 调动信使,在各种物种中发现.
- 传递者介导的Ca2+信号通常涉及从内质网膜释放.
- 通过NAADP调动的特定的Ca2+储存仍然难以捉摸,与内分泌网膜区分开来.
研究的目的:
- 为了确定NAADP在海蛋中准的细胞Ca2+储存.
- 为了阐明NAADP介导的Ca2+释放背后的机制.
- 为了描述这个以前未知的Ca2+储存的性质.
主要方法:
- 利用海蛋作为一个模型系统.
- 使用药理学剂来研究Ca2+调动.
- 进行生物化学分析以确定Ca2+储存的关键成分.
- 评估了质子梯度和真空型质子的作用.
主要成果:
- 证明NAADP从依赖ATP驱动的质子和质子梯度的储存中调动Ca2+ .
- 提供了强有力的证据,确定这种Ca2+储存是储备颗粒.
- 已确立的储备颗粒是海蛋中溶酶体的功能等价物.
- 展示了与溶酶体相关的有机体,作为传递器介导的Ca2+释放的新型来源.
结论:
- 海蛋中的储备颗粒是NAADP动员的以前未被识别的Ca2+储存.
- 从储备颗粒中通过NAADP介导的Ca2+释放取决于由真空型质子维持的质子梯度.
- 这项研究揭示了一种出乎意料的Ca2+信号传递机制,源自溶解体相关的细胞器官.
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