RNA editing in bacteria: occurrence, regulation and significance
RNA editing in bacteria: occurrence, regulation and significance
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DOI：
10.1080/15476286.2018.1481698
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发表时间：
2018-01-01
期刊：
影响因子：
4.1
通讯作者：
Dahan, Orna
中科院分区：
文献类型：
--
作者：
Bar-Yaacov, Dan;Pilpel, Yitzhak;Dahan, Orna
DNA承载着生命的蓝图。然而，存储在DNA中的指令可以在执行之前在RNA水平上进行修改。其中一个过程是RNA编辑，它被证明可以修改许多生物体中的RNA序列。最丰富的修饰是腺苷（A）脱氨为肌苷（I）。反过来，肌苷可以通过核糖体和其他细胞机制如逆转录酶被鉴定为鸟苷（G）。在多细胞生物体中，来自阿达尔（作用于RNA的腺苷脱氨酶）家族的酶介导mRNA中的RNA编辑，而来自ADAT家族的酶介导tRNA上的A至I编辑。然而，在细菌中，直到最近，只有一个编辑位点被描述，在tRNA（Arg）中，但从未在mRNA中。tRNA位点被tadA（tRNA特异性腺苷脱氨酶）修饰，tadA被认为是RNA编辑酶家族的祖先酶。在我们最近的工作中，我们首次展示了细菌mRNA中多个位点的编辑，并确定tadA是负责这种编辑活动的酶。聚焦于其中一个已确定的目标--自我杀伤毒素hokB，我们发现编辑是生理调节的，它增加了蛋白质活性。在这里，我们讨论了hokB编辑的可能调控模式，RNA编辑在细菌中的潜在作用，可能的影响和未来的研究方向。
DNA harbors the blueprint for life. However, the instructions stored in the DNA could be altered at the RNA level before they are executed. One of these processes is RNA editing, which was shown to modify RNA sequences in many organisms. The most abundant modification is the deamination of adenosine (A) into inosine (I). In turn, inosine can be identified as a guanosine (G) by the ribosome and other cellular machineries such as reverse transcriptase. In multicellular organisms, enzymes from the ADAR (adenosine deaminase acting on RNA) family mediate RNA editing in mRNA, whereas enzymes from the ADAT family mediate A-to-I editing on tRNAs. In bacteria however, until recently, only one editing site was described, in tRNA(Arg), but never in mRNA. The tRNA site was shown to be modified by tadA (tRNA specific adenosine deaminase) which is believed to be the ancestral enzyme for the RNA editing family of enzymes. In our recent work, we have shown for the first time, editing on multiple sites in bacterial mRNAs and identified tadA as the enzyme responsible for this editing activity. Focusing on one of the identified targets - the self-killing toxin hokB, we found that editing is physiologically regulated and that it increases protein activity. Here we discuss possible modes of regulation on hokB editing, potential roles of RNA editing in bacteria, possible implications, and future research directions.