在H+/K+-ATPase和细胞膜潜力的不对称性构成左右模式的非常早期阶段
Michael Levin1, Thorleif Thorlin, Kenneth R Robinson
1Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
Cell
|October 10, 2002
概括
质子 (H+和K+ ATPase) 对于在Xenopus胚胎中建立左右不对称的身体至关重要. 破坏这种传送器会随机化身体轴形成和基因表达模式.
科学领域:
- 发展生物学 发展生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 左右 (LR) 身体不对称对于正确的器官定位和功能至关重要.
- 早期LR轴确定背后的分子机制仍然不完全理解.
- 离子运输已经涉及到发育过程,但其在LR不对称性中的具体作用尚不清楚.
研究的目的:
- 调查H+和K+ ATPase载体在确定LR体轴方向方面的作用.
- 为了确定H+和K+ ATPase活性是否在LR跨物种不对称性确定中保持.
主要方法:
- 在Xenopus胚胎中药理上抑制H+和K+ ATPase活性.
- 对mRNA局部化和基因表达模式的分析.
- 评估器官位置和身体轴方向.
主要成果:
- 药理学查发现H+和K+ ATPase对于Xenopus的LR轴方向至关重要.
- 在Xenopus的早期发育过程中,H+和K+ ATPase的mRNA局部化变得不对称.
- 在Xenopus和小胚胎中H+和K+ ATPase的扰乱随机LR不对称性和诱导器官异质性.
结论:
- H+ 和 K+ ATPase 载体在 LR 异对称性确定中起着保留的,关键的作用.
- 由H+和K+ ATPase活动介导的早期差异性离子流是建立LR体轴的基础.
- 这种离子运输机制是不对称的基因表达模式的关键上游调节器.
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