Molecular Genetics of Mammalian Cytochrome c Oxidase

哺乳动物细胞色素 c 氧化酶的分子遗传学

基本信息

批准号：
8905285
负责人：
Lawrence Grossman
金额：
$ 29.8万
依托单位：
Wayne State University School of Medicine
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
1989
资助国家：
美国
起止时间：
1989-09-01 至 1993-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=8905285&HistoricalAwards=false
关键词：
Molecular Genetics Mammalian Cytochrome Oxidase

项目摘要

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.

细胞色素C氧化酶是电子传输链的末端蛋白，由13个亚基的哺乳动物组成，三种由线粒体DNA编码，其余由核DNA编码。除了所有十个核编码亚基的函数尚不清楚的事实外，第二个复杂性还引入了第二个级别的复杂性，即至少三个，甚至可能更多，甚至所有这些核亚基都以多种细胞形式出现（同工型）。我们将（1）关注两个细胞色素C氧化酶，VIIA和VIIC的亚基，它们作为同工型的存在，以（a）分离和表征每种同工型的cDNA，（b）确定这些同工型通过检查其基因组中的转录和编码区域而产生的这些同工型的机制；（2）通过检查其在各种成年牛组织中的转录本的分布以及从几个不同发育阶段采取的组织中，寻求对这些同工型的作用的见解；（3）研究这些和其他细胞色素C氧化酶亚基的调节，我们通过观察培养的牛细胞中的化学计量来进行探测，尤其是在扰动与反义转录物合成特定亚基的（扰动特定亚基）之后。正确组装的复杂蛋白（例如细胞色素C氧化酶）如何晦涩。更神秘的是基因表达同步调节的机制，尤其是当一些位于核基因组上，而另一些位于细胞器基因组上时，因此要组装的亚基的适当评估是结果。这项研究的结果将使我们对这一复杂过程几乎没有更多的了解。