An ortholog of the Ro autoantigen functions in 23S rRNA maturation in D-radiodurans
An ortholog of the Ro autoantigen functions in 23S rRNA maturation in D-radiodurans
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在 D-radiodurans 23S rRNA 成熟过程中发挥功能的 Ro 自体抗原直向同源物
DOI：
10.1101/gad.1548207
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发表时间：
2007-06-01
影响因子：
10.5
通讯作者：
Wolin, Sandra L.
中科院分区：
文献类型：
--
作者：
Chen, Xinguo;Wurtmann, Elisabeth J.;Wolin, Sandra L.
在动物细胞和耐辐射异常球菌中，Ro自身抗原是一种环状RNA结合蛋白，与称为Y RNA的小RNA结合。在脊椎动物中，Ro还结合错误折叠的RNA的3'末端，并被认为在质量控制中起作用。然而，关于Ro和Y RNA在体内的功能知之甚少。在这里，我们报告说，D。radiodurans直系同源物Rsr（Ro sixty related）在23S rRNA成熟中与核糖核酸外切酶一起起作用。在正常生长期间，23S rRNA成熟是低效的，导致含有5'和3'延伸的前体的积累。在高温下生长期间，成熟是有效的，并且需要Rsr和核糖核酸外切酶RNase PH和RNase II。与Y RNA抑制Ro活性的假设一致，在缺乏Y RNA的细胞中，成熟在所有温度下都是有效的。在没有Rsr的情况下，23 S rRNA成熟在潜在二级结构的位置停止。由于Rsr表现出与核糖核酸外切酶多核苷酸磷酸化酶的遗传和生物化学相互作用，Rsr可能在与该核酸酶的另外过程中起作用。我们建议，Rsr的功能作为一个持续因子，以协助RNA成熟的核糖核酸外切酶。这是Ro和Y RNA在体内的作用的第一个证明。
In both animal cells and the eubacterium Deinococcus radiodurans, the Ro autoantigen, a ring-shaped RNA-binding protein, associates with small RNAs called Y RNAs. In vertebrates, Ro also binds the 3' ends of misfolded RNAs and is proposed to function in quality control. However, little is known about the function of Ro and the Y RNAs in vivo. Here, we report that the D. radiodurans ortholog Rsr (Ro sixty related) functions with exoribonucleases in 23S rRNA maturation. During normal growth, 23S rRNA maturation is inefficient, resulting in accumulation of precursors containing 5' and 3' extensions. During growth at elevated temperature, maturation is efficient and requires Rsr and the exoribonucleases RNase PH and RNase II. Consistent with the hypothesis that Y RNAs inhibit Ro activity, maturation is efficient at all temperatures in cells lacking the Y RNA. In the absence of Rsr, 23S rRNA maturation halts at positions of potential secondary structure. As Rsr exhibits genetic and biochemical interactions with the exoribonuclease polynucleotide phosphorylase, Rsr likely functions in an additional process with this nuclease. We propose that Rsr functions as a processivity factor to assist RNA maturation by exoribonucleases. This is the first demonstration of a role for Ro and a Y RNA in vivo.