Molecular Genetics of Mammalian Cytochrome c Oxidase

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13个亚基组成， 三个由线粒体DNA编码，其余的由 核DNA 除了函数是 未知的所有十个核编码亚基，第二个 复杂性的水平已经引入的发现， 至少有三个，可能更多，甚至可能所有这些 核亚单位以一种以上的细胞形式存在 （同种型）。 我们将（1）集中在细胞色素的两个亚基 c氧化酶，VIIa和VIIc，它们作为同种型存在于 为了（a）分离和表征每种同种型的cDNA， 和（B）确定这些异构体产生的机制 通过检查他们的成绩单和他们的组织， 基因组中的编码区;（2）寻求对作用的见解 通过检查这些异构体的分布， 各种成年牛组织中的转录物，以及 来自不同的发展阶段;（3） 研究这些和其他细胞色素c的调节 氧化酶亚基，我们有探针，通过观察他们的 在培养的牛细胞中的化学计量，特别是在 干扰特定亚基的合成， 反义转录物 像细胞色素c氧化酶这样的复杂蛋白质 正确组装是模糊的。 更神秘的是 参与基因同步调控的机制 表达，特别是当一些位于核上时， 基因组和其他细胞器基因组上， 要组装的子单元的定量结果。 的结果 这项研究将使我们更深入地了解这种复杂的 过程

Cytochrome c oxidase, the terminal protein of the electron transport chain, is composed in mammals of thirteen subunits, three encoded by mitochondrial DNA and the remainder by nuclear DNA. In addition to the fact that the function is unknown for all ten of the nuclear-encoded subunits, a second level of complexity has been introduced by the finding that at least three, probably more, and possibly even all of these nuclear subunits occur in more than one cellular form (isoforms). We will (1) focus on two subunits of cytochrome c oxidase, VIIa and VIIc, that are present as isoforms in order to (a) isolate and characterize cDNAs for each isoform, and (b) determine the mechanism by which these isoforms arise by examining their transcripts and the organization of their coding regions in the genome; (2) seek insights into the role of these isoforms by examining the distribution of their transcripts in various adult bovine tissues, and in tissues taken from several different developmental stages; and (3) investigate the regulation of these and other cytochrome c oxidase subunits for which we have probes by observing their stoichiometry in cultured bovine cells, particularly after perturbation of the synthesis of specific subunits with antisense transcripts. How a complex protein such as cytochrome c oxidase is correctly assembled is obscure. Even more mysterious are the mechanisms involved in the synchronous regulation of gene expression, particularly when some are located on the nuclear genome and others on the organelle genome, so that the proper ration of subunits to be assembled results. The results of this study will give us little more insight into that complex process.