Lisowsky T
Botanisches Institut, Heinrich-Heine Universität Düsseldorf, Germany.
Curr Genet. 1994 Jul;26(1):15-20. doi: 10.1007/BF00326299.
In former studies it was found that the ERV1 gene is essential for cell viability and for the biogenesis of functional mitochondria. A temperature-sensitive nuclear mutant exhibits a severe reduction in all the mitochondrial transcripts. Elimination of the gene leads to growth arrest after a few cell divisions. The putative gene product bears the characteristics of a regulatory factor since it has low expression rate and a high content of charged amino acids. In this study it is further verified that the ERV1 gene alone is responsible for the observed cellular and mitochondrial defects. The 5' region of the gene is analysed by DNA deletions and complementation studies. Expression of the gene under the control of the GAL1-10 promoter in a disruption strain of ERV1 allows a more detailed specification ot its influence on mitochondrial and cellular functions. Immediate and complete loss of mitochondrial genomes is observed after the promoter has been shut off, whereas the yeast cells are still able to grow for a limited time under these conditions. Analysis of the cells by in-vivo DNA fluorescence demonstrates a specific arrest in the cell-division cycle as the terminal phenotype. To further characterize the temperature-sensitive allele of ERV1 the mutated gene has been isolated and sequenced. A single point mutation which leads to the exchange of a single amino acid is found in the reading frame.
在以往的研究中发现，ERV1基因对于细胞活力和功能性线粒体的生物合成至关重要。一个温度敏感型核突变体在所有线粒体转录本中都表现出严重减少。该基因的消除会导致细胞分裂几次后生长停滞。假定的基因产物具有调节因子的特征，因为它具有低表达率和高含量的带电荷氨基酸。在本研究中，进一步证实仅ERV1基因就导致了所观察到的细胞和线粒体缺陷。通过DNA缺失和互补研究分析了该基因的5'区域。在ERV1破坏菌株中，在GAL1-10启动子控制下该基因的表达能够更详细地说明其对线粒体和细胞功能的影响。在启动子关闭后，观察到线粒体基因组立即完全丧失，而酵母细胞在这些条件下仍能在有限时间内生长。通过体内DNA荧光对细胞进行分析，显示出细胞分裂周期中的特异性停滞作为终末表型。为了进一步表征ERV1的温度敏感等位基因，已分离并测序了突变基因。在阅读框中发现了一个导致单个氨基酸交换的单点突变。
