NF-AT的激活需要通过氨酸尿素抑制Crm1依赖的出口
1Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Nature
|March 27, 1999
概括
核进口NF-AT转录因子需要氨酸. 氨酸还防止NF-AT出口,通过调节核运输来确保T细胞激活.
科学领域:
- 分子生物学分子生物学
- 免疫学 免疫学 免疫学
- 细胞生物学 细胞生物学
背景情况:
- 核进口NF-AT转录因子对于T细胞激活至关重要.
- 这个过程是由激活的酸酶calcineurin调解的,它揭示了核位置信号.
研究的目的:
- 为了研究NF-AT转录因子在T细胞激活过程中的调节.
- 阐明氨酸在控制NF-AT核运输和基因激活中的作用.
主要方法:
- 研究了NF-AT转录因子的核进出口动态.
- 研究了NF-AT,氨酸和出口中的Crm1.0之间的相互作用.
- 研究了氨酸在调节NF-AT转运中的非催化机制.
主要成果:
- 由于徒劳的循环,NF-AT的核进口不足以激活目标基因.
- 通过Crm1出口NF-AT,这是一个由氨酸抑制的过程.
- 氨酸通过一种非催化机制抑制了Crm1介导的出口,掩盖了核出口信号.
结论:
- 氨酸的非催化功能对于抑制无用的NF-AT循环和使T细胞激活至关重要.
- 在NF-AT上,氨酸和Crm1结合点之间的竞争使对转录因子动态产生敏感性.
- 这种监管平衡可以扩展到核运输中涉及的其他转录因素.
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