Multiple genes, including a member of the AAA family, are essential for degradation of unassembled subunit 2 of cytochrome c oxidase in yeast mitochondria
Multiple genes, including a member of the AAA family, are essential for degradation of unassembled subunit 2 of cytochrome c oxidase in yeast mitochondria
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多个基因，包括 AAA 家族的成员，对于酵母线粒体中细胞色素 c 氧化酶未组装的亚基 2 的降解至关重要
DOI：
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发表时间：
1995
影响因子：
5.3
通讯作者：
Andakira Ohashi
中科院分区：
文献类型：
--
作者：
Toshiki Nakai;T. Yasuhara;Yukio Fujiki;Andakira Ohashi
细胞色素 c 氧化酶由三个线粒体和几个细胞核编码亚基组成。我们之前发现，在缺乏该酶核编码亚基4（CoxIV）的酿酒酵母突变体中，由线粒体DNA编码的亚基2和亚基3（CoxII和CoxIII）不稳定并在线粒体中快速降解，可能是因为亚基无法正常组装。为了分析参与该蛋白水解途径的分子机制，我们通过筛选 CoxIV 缺陷细胞的 CoxII 积累，获得了四种未组装的 CoxII 降解缺陷的突变体（osd 突变体）。所有突变体都是隐性的，并被分为三个不同的互补组。四分体分析表明，每个突变体的表型都是由单个核突变引起的。这些结果强烈表明该降解系统至少需要三个核基因（OSD 基因）。有趣的是，CoxIII 的降解在突变体中没有受到影响，这意味着这两个亚基是通过不同的途径降解的。我们还通过在不可发酵甘油培养基上补充具有 COXIV+ 遗传背景的 osd1-1 突变体的温度敏感性来克隆 OSD1 基因。我们发现它编码假定的 ATP 酶家族（AAA 家族）的一个成员，该家族被证明与最近描述的 YME1 和 YTA11 相同。免疫学分析表明，Osd1 蛋白定位于线粒体内膜。通过定点诱变破坏预测的 ATP 结合盒消除了生物活性，从而强调了 ATP 对于功能的重要性。
Cytochrome c oxidase consists of three mitochondrion- and several nucleus-encoded subunits. We previously found that in a mutant of Saccharomyces cerevisiae lacking nucleus-encoded subunit 4 of this enzyme (CoxIV), subunits 2 and 3 (CoxII and CoxIII), both encoded by the mitochondrial DNA, were unstable and rapidly degraded in mitochondria, presumably because the subunits cannot assemble normally. To analyze the molecular machinery involved in this proteolytic pathway, we obtained four mutants defective in the degradation of unassembled CoxII (osd mutants) by screening CoxIV-deficient cells for the accumulation of CoxII. All of the mutants were recessive and were classified into three different complementation groups. Tetrad analyses revealed that the phenotype of each mutant was caused by a single nuclear mutation. These results suggest strongly that at least three nuclear genes (the OSD genes) are required for this degradation system. Interestingly, degradation of CoxIII was not affected in the mutants, implying that the two subunits are degraded by distinct pathways. We also cloned the OSD1 gene by complementation of the temperature sensitivity of osd1-1 mutants with a COXIV+ genetic background on a nonfermentable glycerol medium. We found it to encode a member of a family (the AAA family) of putative ATPases, which proved to be identical to recently described YME1 and YTA11. Immunological analyses revealed that Osd1 protein is localized to the mitochondrial inner membrane. Disruption of the predicted ATP-binding cassette by site-directed mutagenesis eliminated biological activities, thereby underscoring the importance of ATP for function.
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DOI：
10.1016/s0021-9258(17)42340-4
发表时间：
1994-01
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
L. van Dyck;D. Pearce;F. Sherman
通讯作者：
L. van Dyck;D. Pearce;F. Sherman
牛肾上腺皮质中的 ATP 依赖性蛋白酶。
DOI：
--
发表时间：
1985
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Watabe,S;Kimura,T
通讯作者：
Kimura,T
酿酒酵母的核突变影响 DNA 从线粒体逃逸到细胞核。
影响因子：
3.3
作者：
Thorsness,PE;Fox,TD
通讯作者：
Fox,TD
DOI：
10.1073/pnas.85.21.7852
发表时间：
1988-11-01
影响因子：
11.1
作者：
BLOCK, MR;GLICK, BS;ROTHMAN, JE
通讯作者：
ROTHMAN, JE
酵母细胞色素 c 氧化酶的 VIa 亚基对于酶复合物的组装不是必需的，但可以调节酶活性。
DOI：
--
发表时间：
1993
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Taanman,JW;Capaldi,RA
通讯作者：
Capaldi,RA