Faculty of Bioengineering and Bioinformatics, Moscow State University, Vorobyevy Gory 1, Moscow, Russia.
Eur J Cell Biol. 2013 Apr-May;92(4-5):169-74. doi: 10.1016/j.ejcb.2013.02.001. Epub 2013 Mar 13.
Stressed Saccharomyces cerevisiae cells easily lose respiratory function due to deletions in mitochondrial DNA, and this increases their general stress resistance. Is the loss active? We found that erythromycin (an inhibitor of mitochondrial translation) prevents the loss in control cells but not in the ones expressing mitochondrially-encoded protein Var1 in the nucleus. Var1 is a component of mitochondrial ribosomes; it is hydrophilic, positively charged, and prone to aggregation. Addition of DNase altered Var1 content in a preparation of mitochondrial nucleoids. Our data indicate that Var1 physically interacts with mitochondrial DNA and under stress negatively regulates its maintenance.
压力下的酿酒酵母细胞由于线粒体 DNA 的缺失很容易失去呼吸功能，这提高了它们的总体应激抗性。这种缺失是主动发生的吗？我们发现，红霉素（一种线粒体翻译抑制剂）可以阻止对照细胞中的缺失，但不能阻止核中转录 Var1 的细胞中的缺失。Var1 是线粒体核糖体的组成部分；它具有亲水性、正电荷和易于聚集的特点。加入 DNA 酶改变了线粒体类核制剂中 Var1 的含量。我们的数据表明，Var1 与线粒体 DNA 发生物理相互作用，并在应激条件下负调控其维持。
