德国哥廷根大学Peter Rehling课题组开发出一种抑制线粒体基因表达的体外系统。相关论文于2021年10月20日在线发表在《细胞》杂志上。

研究人员提出了一个体外系统来沉默纯化线粒体中的翻译。在体外导入化学合成的前体-吗啉杂交体能够针对单个线粒体mRNA的翻译。通过应用这种方法，研究人员发现，双顺反子的、重叠的ATP8/ATP6转录本是通过单一核糖体/mRNA的参与而翻译的。结果表明，COX1组装因子对翻译核糖体的招募取决于新生链的形成。通过定义COX1和COX2的mRNA特异性相互作用组，研究人员揭示了细胞膜上的IGF2BP1（一种RNA结合蛋白）在线粒体翻译中的意外功能。这些数据提供了对线粒体翻译的深入了解，以及研究线粒体基因表达的创新策略。

据介绍，人类线粒体基因组编码氧化磷酸化系统的13个核心亚单位，线粒体基因表达的缺陷导致严重的神经肌肉疾病。然而，由于缺乏分析这些过程的实验方法，对线粒体基因表达的机制仍然知之甚少。

附：英文原文

Title: An in vitro system to silence mitochondrial gene expression

Author: Luis Daniel Cruz-Zaragoza, Sven Dennerlein, Andreas Linden, Roya Yousefi, Elena Lavdovskaia, Abhishek Aich, Rebecca R. Falk, Ridhima Gomkale, Thomas Schndorf, Markus T. Bohnsack, Ricarda Richter-Dennerlein, Henning Urlaub, Peter Rehling

Issue&Volume: 2021-10-20

Abstract: The human mitochondrial genome encodes thirteen core subunits of the oxidative phosphorylation system, and defects in mitochondrial gene expression lead to severe neuromuscular disorders. However, the mechanisms of mitochondrial gene expression remain poorly understood due to a lack of experimental approaches to analyze these processes. Here, we present an in vitro system to silence translation in purified mitochondria. In vitro import of chemically synthesized precursor-morpholino hybrids allows us to target translation of individual mitochondrial mRNAs. By applying this approach, we conclude that the bicistronic, overlapping ATP8/ATP6 transcript is translated through a single ribosome/mRNA engagement. We show that recruitment of COX1 assembly factors to translating ribosomes depends on nascent chain formation. By defining mRNA-specific interactomes for COX1 and COX2, we reveal an unexpected function of the cytosolic oncofetal IGF2BP1, an RNA-binding protein, in mitochondrial translation. Our data provide insight into mitochondrial translation and innovative strategies to investigate mitochondrial gene expression.

DOI: 10.1016/j.cell.2021.09.033

Source: https://www.cell.com/cell/fulltext/S0092-8674(21)01116-8