MOLECULAR GENETICS OF MAMMALIAN CYTOCHROME C OXIDASE

描述：细胞色素c氧化酶，电子的末端蛋白 运输链，在哺乳动物中由十三个亚基组成，三个亚基 由线粒体 DNA 编码，十个由核 DNA 编码。至少其中三个 这些核亚基以不止一种分子形式（亚型）出现， 不同基因的产物。拟议的实验将提供 对这些亚型的细胞功能的深入了解，这可能是 与个体发育和细胞生理学相关。在 此外，异构体的表达与人类神经肌肉 疾病。该项目将重点关注三个已经分离的基因， 编码两个亚基：COX VIIa 和 COX VIIc。 亚基 VIIa 显示 心脏/肌肉特异性同种型 (H) 和在所有细胞中表达的同种型 (L) 组织。第二个亚基 VIIc 似乎具有单一表达形式 所有组织。具体目标是（1）表征核心启动子 COX7AL、COX7AH 和 COX7C 基因中的相互作用； (2) 确定 启动子远端序列和因子在调控事件中的作用 发生在 COX7AL、COX7AH 和 COX7C 核心启动子处，通过 (a) 识别 核心启动子远端的新调控位点，(b) 识别新的 酵母一、二杂交体应用的调控位点和因子 技术，以及（c）确定新监管因素的影响 与核心启动子事件的结合，以及远端 DNA 的影响 序列本身； (3) 阐明启动子在细胞中的功能 发展和分化。该项目符合长期目标 推断核编码亚基的作用和 用于调节氧化功能的机制，并应用该机制 线粒体疾病核基因研究的知识。

DESCRIPTION: Cytochrome c oxidase, the terminal protein of the electron transport chain, is composed in mammals of thirteen subunits, three encoded by mitochondrial DNA and ten by nuclear DNA. At least three of these nuclear subunits occur in more than one molecular form (isoforms), the products of separate genes. The proposed experiments will provide insights into the cellular function of these isoforms, which may be related to both ontogenetic development and cellular physiology. In addition, isoform expression has been implicated in human neuromuscular disease. This project will focus on three genes, already isolated, that encode two subunits, COX VIIa and COX VIIc. Subunit VIIa displays a heart/muscle-specific isoform (H) and an isoform (L) expressed in all tissue. A second subunit, VIIc, appears to have a single expressed form in all tissues. The specific aims are to (1) characterize the core promoter interactions in the COX7AL, COX7AH, and COX7C genes; (2) determine the roles of promoter-distal sequences and factors in regulatory events that occur at the COX7AL, COX7AH, and COX7C core promoters by (a) identifying new regulatory sites that are core promoter distal, (b) identifying new regulatory sites and factors by application of yeast one-and two-hybrid technologies, and (c) determining the effect of new regulatory factor binding on events at the core promoter, and also the effect of distal DNA sequences per se; and (3) elucidating promoter function in cell development and differentiation. This project fits into the longer term objectives of deducing the role of the nuclear-encoded subunits and the mechanisms used to regulated oxidative function, and applying this knowledge to the study of nuclear genes in mitochondrial disease.