Defective splicing of the first nad4 intron is associated with lack of several complex I subunits in the Nicotiana sylvestris NMS1 nuclear mutant
Defective splicing of the first nad4 intron is associated with lack of several complex I subunits in the Nicotiana sylvestris NMS1 nuclear mutant
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DOI：
10.1046/j.1365-313x.2000.00679.x
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发表时间：
2000-02-01
期刊：
影响因子：
7.2
通讯作者：
De Paepe, R
中科院分区：
文献类型：
--
作者：
Brangeon, J;Sabar, M;De Paepe, R
在这项工作中，我们提供的证据，在高等植物中的一个特定的线粒体内含子的剪接参与的核因子的存在。在欧洲林烟草核NMS1突变体，营养和生殖发育缺陷，第一内含子的nad4转录编码的复合体I NAD4亚基没有被删除，无论分析的组织。其他标准线粒体基因的转录模式在NMS 1中不受影响。然而，许多多肽在细胞器线粒体蛋白质合成模式的二维中缺失，并且几个核和线粒体复合物I亚基以痕量存在。这表明其他线粒体蛋白质合成中的翻译或翻译后步骤受到影响。所有这些缺陷与NMS1 ×野生型杂交后代中的异常表型共分离，表明它们由相同的核基因（MS1）或紧密连锁的基因座控制。这种复杂的情况已经在真菌的叶绿体和线粒体中描述过，但从未在高等植物线粒体中描述过。
In this work, we provide evidence for the existence of a nuclear factor involved in the splicing of a specific mitochondrial intron in higher plants. In the Nicotiana sylvestris nuclear NMS1 mutant, defective in both vegetative and reproductive development, the first intron of the nad4 transcript encoding the complex I NAD4 subunit is not removed, whatever the tissue analysed. Transcript patterns of other standard mitochondrial genes are not affected in NMS1. However, numerous polypeptides are missing in two-dimensional in organello mitochondrial protein synthesis patterns and several nuclear and mitochondrial complex I subunits are present in trace amounts. This indicates that translational or post-translational steps in the synthesis of other mitochondrial proteins are affected. All of these defects co-segregated with the abnormal phenotype in the offspring of a NMS1 x wild-type cross, showing that they are controlled by the same nuclear gene (MS1) or tightly linked loci. Such a complex situation has been described in chloroplasts and mitochondria of fungi, but never in higher plant mitochondria.