Modification of 16S ribosomal RNA by the KsgA methyltransferase restructures the 30S subunit to optimize ribosome function
Modification of 16S ribosomal RNA by the KsgA methyltransferase restructures the 30S subunit to optimize ribosome function
复制标题
DOI：
10.1261/rna.2357210
复制
发表时间：
2010-12-01
期刊：
影响因子：
4.5
通讯作者：
Jogl, Gerwald
中科院分区：
文献类型：
--
作者：
Demirci, Hasan;Murphy, Frank;Jogl, Gerwald
所有生物体都将转录后修饰并入核糖体RNA，以知之甚少的方式影响核糖体组装和功能。最高度保守的修饰是小亚基rRNA的39末端附近的两个腺苷的二甲基化。由于KsgA甲基转移酶的缺陷而缺乏这些甲基化会刺激蛋白质合成的起始和延伸阶段期间的翻译错误，并赋予对抗生素春雷霉素的抗性。在这里，我们提出的X射线晶体结构的嗜热栖热菌30S核糖体亚基缺乏这些二甲基化。我们的数据表明，KsgA指导的甲基化促进结构重排，以建立一个功能最佳的亚基构象在核糖体组装的最后阶段。
All organisms incorporate post-transcriptional modifications into ribosomal RNA, influencing ribosome assembly and function in ways that are poorly understood. The most highly conserved modification is the dimethylation of two adenosines near the 39 end of the small subunit rRNA. Lack of these methylations due to deficiency in the KsgA methyltransferase stimulates translational errors during both the initiation and elongation phases of protein synthesis and confers resistance to the antibiotic kasugamycin. Here, we present the X-ray crystal structure of the Thermus thermophilus 30S ribosomal subunit lacking these dimethylations. Our data indicate that the KsgA-directed methylations facilitate structural rearrangements in order to establish a functionally optimum subunit conformation during the final stages of ribosome assembly.