欧核生物和阿斯加德古生物的核糖体转移机械的互容性
Isaac Carilo1, Yosuke Senju1, Takeshi Yokoyama2
1Research Institute for Interdisciplinary Science (RIIS), Okayama University, Okayama, Japan.
The Journal of biological chemistry
|August 11, 2024
概括
这项研究揭示了蛋白质运输必不可少的核糖体 - 转环复合体如何在真核生成过程中迁移到内质网膜. 这种蛋白质水平的机制解释了这些重要细胞机械的进化转移.
科学领域:
- 细胞生物学 细胞生物学
- 进化生物学 进化生物学
- 生物化学 生物化学
背景情况:
- 核糖体-转位元复合体调解所有生命形式的蛋白质插入和跨膜转位.
- 细胞的转位子位于内质网膜中,而 prokaryotic 的转位子位于细胞膜中.
- 细胞转位子单元可以追溯到阿斯加德古生物,但它们的迁移机制尚不清楚.
研究的目的:
- 在真核生成过程中,研究从细胞膜到原生态内膜网膜的跨位元复合物迁移的机制.
- 探索真核核糖核糖体和阿斯加德古生物蛋白质之间的兼容性.
- 了解如何建立和传播跨位子位置.
主要方法:
- 对跨位元子单元的遗传学分析.
- 在真核细胞中,阿斯加德古人类转位蛋白的异胎表达.
- 生物化学测试来测试核糖体-转基因相互作用.
主要成果:
- 细胞核糖体与阿斯加德信号和跨膜蛋白质兼容.
- 来自Lokiarchaeon (Candidatus Prometheoarchaeum syntrophicum MK-D1) 的阿斯加德转位蛋白在异位表达时准了内分泌网膜.
- 一个阿斯加德古老的细胞质域的寡糖转移酶1 (ribophorin I) 与真核细胞的核糖体相互作用.
结论:
- 通过现有的复合体,在蛋白质水平上确定了转位孔复合体的位置.
- 这一原理解释了转位子迁移在真核生成过程中传播到原核细胞网膜的原理.
- 一些迁移的跨位子复合体可能推动了进化转变,导致它们从细胞膜中消失.
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