Heme A and cytochrome oxidase biosynthesis

血红素 A 和细胞色素氧化酶生物合成

• 批准号: 7499598
• 负责人: ALEXANDER A TZAGOLOFF
• 金额: $ 25.91万
• 依托单位: COLUMBIA UNIV NEW YORK MORNINGSIDE
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-01-15 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7499598
• 关键词: Anabolism; Binding; Biochemical Genetics; Biogenesis; Catalytic Domain; Cells; Chemicals; Collection; Complex; Copper; Defect; Disease; Enzymes; Eukaryotic Cell; Fibroblasts; Functional disorder; Genes; Genome; Goals; Grant; Heme; Heterogeneous Nuclear RNA; Homeostasis; Homologous Gene; Human; Hydroxylation; In Vitro; Investigation; Laboratories; Learning; Mechanics; Membrane; Metals; Methods; Mitochondria; Mitochondrial RNA; Mixed Function Oxygenases; Mutation; Nuclear; Numbers; Oxidases; PTGS1 gene; Pathway interactions; Patients; Play; Process; Property; Proteins; Regulation; Research Personnel; Respiratory Chain; Role; Saccharomyces cerevisiae; Staging; Time; Transcript; Translations; Work; Yeasts; alternative oxidase; c new; cyclooxygenase 1; cytochrome c; cytochrome c oxidase; gene function; heme O; heme biosynthesis; improved; in vitro Assay; in vivo; mRNA Precursor; membrane activity; mutant; oxidation; polypeptide; programs; respiratory; stem

DESCRIPTION (provided by applicant): Yeast cytochrome c oxidase (COX), the terminal complex of the mitochondrial respiratory chain, is composed of 12 different polypeptides. The three subunits constituting the catalytic core of the complex are encoded by mitochondrial genes. The remaining 8 subunits are products of the nuclear genome. Biogenesis of this important enzymes is governed by more than three dozen genes that intercede at all stages of the assembly pathway. The functions of these genes have been and continue to be the focus of this project. During the past grant period we have 1) completed studies on Scolp and Cox15p that function in maturation of the CuA center in subunit 2 and biosynthesis of heme A, respectively, 2) identified and studied the functions of 4 new COX-specific genes, 3) shown that cytochrome c is required in a structural capacity for COX assembly, 4) identified a ternary complex of Cox14p, Mss51p, and Coxlp involved in regulation of Coxlp translation, 5) collaborated with Dr. Pierre Rustin on studies of patients with COX dysfunctions. In the present application we propose to continue investigations of COX deficient mutants to gain a better understanding of the process by which COX is assembled. These studies will aim to clarify how Shylp functions in the regulatory circuit that coordinates the synthesis of subunit 1 to its utilization for COX assembly. Another aim is to explore the roles of the mitochondrial intermembrane metallo-proteins Cox23p, Cox19p, and Pet191 p in maturation of the copper centers of COX. These studies will examine copper transfer from these intermembrane proteins to Cox17p and whether any of them are present in a common complexe(s)? Studies on Cox15p, the heme O hydroxylase of mitochondria, were hampered by problems encountered in our attempts to purify the protein. The most serious of these difficulties have been resolved and we expect to obtain a purified Cox15p suitable for the in vitro enzymatic studies that had been planned earlier. Concurrently, we will extend our functional analyses to new and partially characterized COX-specific genes by combined biochemical and genetic approaches used in the past. Finally, we will continue to collaborate with the Rustin lab on studies of human disorders stemming from defective COX. These studies will strive to use an alternative oxidase to rescue COX mutants and to improve on current methods for assigning human mutations to known COX genes.

描述(申请人提供)：酵母细胞色素c氧化酶(COX)，线粒体呼吸链的末端复合体，由12种不同的多肽组成。组成该复合体催化核心的三个亚基由线粒体基因编码。剩下的8个亚基是核基因组的产物。这种重要酶的生物发生是由30多个基因控制的，这些基因参与了组装途径的所有阶段。这些基因的功能一直是并将继续是该项目的重点。在过去的资助期间，我们已经完成了1)分别在亚单位2的CUA中心成熟和血红素A的生物合成中发挥作用的SCOP和Cox15p的研究，2)鉴定和研究了4个新的COX特异基因的功能，3)证明细胞色素c是COX组装所必需的结构能力，4)鉴定了参与Coxlp翻译调控的Cox14p、Mss 51p和Coxlp的三元复合体，5)与Pierre Rustin博士合作研究了COX功能障碍的患者。在本申请中，我们建议继续研究COX缺失突变体，以更好地了解COX的组装过程。这些研究将旨在阐明Shylp如何在调节回路中发挥作用，该回路协调亚基1的合成，并将其用于COX组装。另一个目的是探讨线粒体膜间金属蛋白Cox23p、Cox19p和Pet191 p在COX铜中心成熟过程中的作用。这些研究将检测从这些膜间蛋白到Cox17p的铜转移，以及它们中是否有任何一个存在于共同的络合物中(S)？对线粒体的血红素O羟基酶Cox15p的研究，由于我们在尝试纯化该蛋白质时遇到的问题而受到阻碍。其中最严重的困难已经解决，我们希望获得适合于先前计划的体外酶研究的纯化的Cox15p。同时，我们将通过过去使用的生化和遗传学相结合的方法，将我们的功能分析扩展到新的和部分表征的COX特异性基因。最后，我们将继续与Rustin实验室合作，研究由COX缺陷引起的人类疾病。这些研究将努力使用一种替代的氧化酶来拯救COX突变，并改进目前将人类突变分配给已知COX基因的方法。