在线粒体透性过渡孔中,ADP/ATP转位器并不必不可少
Jason E Kokoszka1, Katrina G Waymire, Shawn E Levy
1Center for Molecular and Mitochondrial Medicine and Genetics, University of California, Irvine, California 92697, USA.
Nature
|January 30, 2004
概括
氨酸核酸转位器 (ANTs) 在亡过程中对线粒体透性过渡孔 (mtPTP) 的形成不必. 虽然ANT调节mtPTP激活,但它们的缺失并不能阻止细胞死亡信号传递.
科学领域:
- 线粒体生物学 线粒体生物学
- 细胞死亡途径的细胞死亡途径.
- 生物化学 生物化学
背景情况:
- 线粒体透性过渡孔 (mtPTP) 是细胞亡的核心.
- 腺核酸转位器 (ANTs) 是mtPTP的组成部分,它们将ATP与ADP交换.
- 可能参与调节细胞死亡.
研究的目的:
- 研究ANT在mtPTP形成和功能中的作用.
- 为了确定ANTs是否对mtPTP介导的亡至关重要.
主要方法:
- 在小鼠肝脏中,ANT异型的遗传失活化.
- 在孤立的线粒体中对mtPTP激活的分析.
- 在肝细胞中诱导细胞死亡的评估.
主要成果:
- 缺乏ANT的线粒体仍然可以经历透性过渡并释放细胞染色体c.
- 需要增加Ca2+来激活mtPTP在缺乏ANT的线粒体中.
- 在它们的缺席下,ANT连接物不能再调节mtPTP.
- 缺乏ANT的肝细胞仍然对诱导细胞死亡的诱导剂有反应.
结论:
- 是mtPTP的非必不可少的结构部件.
- 在mtPTP的激活和功能中起着调节作用.
- 没有ANT并不取消apoptotic过程.
相关概念视频
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Nuclear encoded mitochondrial precursors are imported to the inner membrane in a multistep process involving two separate translocons, TIM22 and TIM23. TIM23 is a cation-selective pore that remains closed by the N terminal segment of the protein. Negative charges on the TIM23 act as a receptor for the incoming precursor, pulling the positively charged matrix-targeting sequence for peptide insertion and translocation.
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