Import into mitochondria, folding and retrograde movement of fumarase in yeast
Import into mitochondria, folding and retrograde movement of fumarase in yeast
复制标题
DOI：
10.1074/jbc.273.40.25587
复制
发表时间：
1998-10-02
影响因子：
4.8
通讯作者：
Pines, O
中科院分区：
文献类型：
--
作者：
Knox, C;Sass, E;Pines, O
FUM1基因编码的一个翻译产物分布在酿酒酵母的胞质溶胶和线粒体之间。所有的线粒体酶翻译产物在分布之前在线粒体中被靶向和加工。在这里，我们表明，靶向的翻译，并最初涉及插入的蛋白质穿过线粒体膜和处理的基质蛋白酶，快速折叠的翻译酶可能会决定其需要耦合的易位与翻译和独特的分布途径。大多数酶分子的氨基末端跨线粒体膜移位并被加工。与这些分子释放到胞质溶胶中的体内情况不同，在体外它们保持外部附着于线粒体，从而定位用于从细胞器释放。我们的模型表明，蛋白酶显示出一种独特的靶向和分布机制，这是协同发生的，涉及折叠和逆行运动的加工蛋白回到通过易位孔。
A single translation product of the FUM1 gene encoding fumarase is distributed between the cytosol and mitochondria of Saccharomyces cerevisiae. All fumarase translation products are targeted and processed in mitochondria before distribution. Here we show that targeting of fumarase is coupled to translation and initially involves insertion of the protein across the mitochondrial membranes and processing by the matrix protease, Rapid folding of fumarase may determine its requirement for coupling of its translocation with translation and unique route of distribution. The amino termini of most fumarase molecules are translocated across the mitochondrial membranes and processed. Unlike the in vivo situation where these molecules are released into the cytosol, in vitro they remain externally attached to the mitochondria, thereby positioned for release from the organelle. Our model suggests that fumarase displays a unique mechanism of targeting and distribution, which occurs cotranslationally and involves folding and retrograde movement of the processed protein back through the translocation pore.