Control of Mitochondrial Cox1 Synthesis by Nuclear Encoded Mss51 and Cox14

描述（由申请方提供）：Chrome c氧化酶合成所需的基因突变损害细胞能量产生。SURF 1是细胞色素c氧化酶组装途径所需的一种蛋白质，在Leigh综合征患者中发生突变。通过鉴定和表征酿酒酵母SHY 1中的SURF 1同源物来促进SURF 1的鉴定。S.作为兼性厌氧菌的酿酒酵母是研究细胞色素C氧化酶组装的极好生物，因为破坏线粒体能量产生的遗传改变不是致命的。此外，核和线粒体DNA可以通过遗传转化被操纵并掺入细胞中。 在这个项目中，S。酿酒酵母将被用来研究两个核编码的蛋白质，Mss 51和Cox 14，如何调节神经编码的Cox 1翻译。这项研究的重要性是强调了一个事实，即在S。酿酒酵母可以抑制由shy 1？引起的细胞色素c氧化酶缺陷。此外，在人类和小鼠基因组中已鉴定出Mss 51的明显直系同源物，其功能仍有待确定。Cox 14是另一种调节Cox 1合成的核编码蛋白。这种调节被认为是通过控制可用于启动Cox 1翻译的Mss 51的量而发生的。基于以前的工作，假设Mss 51，Cox 1和Cox 14作为一系列动态组装复合物存在，这些复合物依赖于Cox 1合成和细胞色素c氧化酶组装的需求，并且Cox 14对于在不存在COX 1编码区侧翼的COX 1非翻译区的情况下Mss 51-Cox 1相互作用的稳定是必不可少的。 在本项目中，蓝色天然凝胶电泳将用于目标1，以鉴定启动Cox 1翻译所需的Mss 51、Cox 1和Cox 14蛋白复合物，稳定未组装的Cox 1，并鉴定Cox 1翻译被组装反馈抑制的菌株中存在的复合物。标记Cox 1合成与35 S和免疫共沉淀研究将用于目的2调查的矛盾抑制Cox 14？不具有侧接COX 1编码序列的COX 1非翻译区的菌株。 这项工作将定义特定的Mss 51，Cox 1和Cox 14蛋白质的相互作用，需要Cox 1的合成。确定这些调节Cox 1合成的相互作用是研究这些复合物如何在Leigh综合征患者中改变的第一步。这反过来又可能导致早期诊断或治疗患者的药物靶点。

DESCRIPTION (provided by applicant): Mutations in genes needed for chrome c oxidase synthesis compromise cellular energy production. SURF1 is one protein needed for the cytochrome c oxidase assembly pathway that is mutated in patients with Leigh syndrome. Identification of SURF1 was facilitated by identifying and characterizing a SURF1 homolog in Saccharomyces cerevisiae, SHY1. S. cerevisiae, being a facultative anaerobe, is an excellent organism to study cytochrome c oxidase assembly, since genetic alterations disrupting mitochondrial energy production are not lethal. Also, nuclear and mitochondrial DNA can be manipulated and incorporated into the cell through genetic transformation. In this project S. cerevisiae will be used to study how two nuclear encoded proteins, Mss51 and Cox14, regulate mitochondrially encoded Cox1 translation. The importance of this study is underscored by the fact that MSS51 mutations in S. cerevisiae can suppress the cytochrome c oxidase defect caused by a shy1?. Also, an apparent ortholog of Mss51 has been identified in the human and mouse genomes with its function remaining to be determined. Cox14 is another nuclear encoded protein that regulates Cox1 synthesis. This regulation is thought to occur by controlling the amount of Mss51 available for initiating Cox1 translation. Based on previous work it is hypothesized that Mss51, Cox1 and Cox14 exist as a series of dynamic assembly complexes that are dependent on the demand for Cox1 synthesis and cytochrome c oxidase assembly, and that Cox14 is essential for the stabilization of the Mss51-Cox1 interaction in the absence of the COX1 untranslated regions flanking the C0X1 coding region. In this project blue native gel electrophoresis will be used in Aim 1 to identify Mss51, Cox1 and Cox14 protein complexes needed for initiating Cox1 translation, stabilizing unassembled Cox1 and identify complexes present in strains where Cox1 translation is assembly feedback inhibited. Labeling Cox1 synthesis with 35S and co-immunoprecipitation studies will be used in Aim 2 to investigate the paradoxical inhibition of Cox1 synthesis in cox14? strains that do not have the COX1 untranslated regions flanking the COX1 coding sequence. This work will define specific Mss51, Cox1 and Cox14 protein interactions that are needed for Cox1 synthesis. Identifying these interactions that regulate Cox1 synthesis is a first step in studying how these complexes may be altered in Leigh syndrome patients. This in turn could potentially result in earlier diagnostics or drug targets to treat patients.