首页> 外文OA文献 >Genetic screening in Saccharomyces cerevisiae for large numbers of mitochondrial point mutations which affect structure and function of catalytic subunits of cytochrome-c oxidase.
【2h】

Genetic screening in Saccharomyces cerevisiae for large numbers of mitochondrial point mutations which affect structure and function of catalytic subunits of cytochrome-c oxidase.

机译:在酿酒酵母中进行遗传筛选,以检测大量线粒体点突变,这些突变影响细胞色素C氧化酶催化亚基的结构和功能。

摘要

A new search for mitochondrial respiratory deficient mutants (Mit-) has been undertaken in order to accumulate a large number of point mutations in the coding portions of cytochrome-c-oxidase catalytic subunits and cytochrome b. Therefore, a mitochondrial DNA which retains the exons and lacks all the introns of the cytochrome oxidase subunit I and of the cytochrome-b split genes has been introduced into a strain carrying a nuclear recessive mutation affecting the adenine-nucleotide translocator, the op1 mutation, which is known to prevent the accumulation of large deletion petite mutants and this was used as the parental strain. After a moderate MnCl2 mutagenesis in order to limit multiple mutations, 105 Mit- mutants were isolated from 15,000 mutagenised clones in Saccharomyces cerevisiae. Mutations were mapped to the three catalytic subunits encoding genes (COX1, COX2 and COX3) of the cytochrome-c oxidase (70 mutations) and to the cytochrome-b gene (15 mutations). More than 50% of the mutants tested still exhibited mitochondrial translation products (subunits I, II and III), suggesting that they carry a missense mutation, rather than a nonsense mutation which would normally have led to a truncated protein. Mutations in the COX1 gene were allocated to four different subregions corresponding to exons 4 and 8 or to groups of exons, exons 1, 2, 3 or exons 5, 6, 7. Seven missense monosubstitution mutations and two frameshift mutations were also identified. The amino acid changes of the missense mutations were located in the vicinity of the CuB-heme alpha 3 binuclear centre ligands.
机译:为了在细胞色素c氧化酶催化亚基和细胞色素b的编码部分中积累大量点突变,已经进行了针对线粒体呼吸缺陷型突变体(Mit-)的新搜索。因此,已将保留外显子且缺少细胞色素氧化酶亚基I和细胞色素b分裂基因的所有内含子的线粒体DNA引入携带核隐性突变的菌株,该突变影响腺嘌呤核苷酸易位子,即op1突变,众所周知,它可以防止大量缺失的小突变体的积累,并将其用作亲本菌株。为了限制多个突变而进行中等程度的MnCl2诱变后,从酿酒酵母中的15,000个诱变克隆中分离出105个Mit突变体。突变被映射到编码细胞色素c氧化酶的基因(COX1,COX2和COX3)的三个催化亚基(70个突变)和细胞色素b基因(15个突变)。超过50%的测试突变体仍显示线粒体翻译产物(亚基I,II和III),表明它们带有错义突变,而不是通常会导致蛋白质被截断的无义突变。 COX1基因中的突变被分配到与外显子4和8或外显子,外显子1、2、3或外显子5、6、7对应的四个不同的亚区域。还鉴定了七个错义单取代突变和两个移码突变。错义突变的氨基酸变化位于CuB-血红素α3双核中心配体附近。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号