An aminoacylation ribozyme evolved from a natural tRNA-sensing T-box riboswitch
An aminoacylation ribozyme evolved from a natural tRNA-sensing T-box riboswitch
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DOI：
10.1038/s41589-020-0500-6
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发表时间：
2020-03-23
影响因子：
14.8
通讯作者：
Suga, Hiroaki
中科院分区：
文献类型：
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作者：
Ishida, Satoshi;Terasaka, Naohiro;Suga, Hiroaki
当原始翻译系统首次出现在假设的RNA世界时，核酶可能负责氨基酰化。鉴于天然存在的T-box核开关选择性地感知同源trna的氨基酰化状态，我们在T-box- trna偶联物中引入了一个随机序列结构域，并分离出在3'端羟基上自我氨基酰化的核酶。其中一个名为Tx2.1，通过与tRNA的茎I结构域的相互作用识别tRNA的反密码子和d环，类似于亲本T-box，并选择性地将n -生物素-L-苯丙氨酸（Bio-(L)Phe）转移到同源tRNA的3'端。我们还证明了在Tx2.1偶联的体外翻译系统中，Bio-(L) phee启动肽的核糖体合成，其中Tx2.1在原位催化特异性tRNA氨基酰化。这表明，这种核酶可能与RNA世界中的原始翻译系统共同进化。
When the primitive translation system first emerged in the hypothetical RNA world, ribozymes could have been responsible for aminoacylation. Given that naturally occurring T-box riboswitches selectively sense the aminoacylation status of cognate tRNAs, we introduced a domain of random sequence into a T-box-tRNA conjugate and isolated ribozymes that were self-aminoacylating on the 3'-terminal hydroxyl group. One of them, named Tx2.1, recognizes the anticodon and D-loop of tRNA via interaction with its stem I domain, similarly to the parental T-box, and selectively charges N-biotinyl-L-phenylalanine (Bio-(L)Phe) onto the 3' end of the cognate tRNA in trans. We also demonstrated the ribosomal synthesis of a Bio-(L)Phe-initiated peptide in a Tx2.1-coupled in vitro translation system, in which Tx2.1 catalyzed specific tRNA aminoacylation in situ. This suggests that such ribozymes could have coevolved with a primitive translation system in the RNA world.