Effect of 3′ terminal adenylic acid residue on the uridylation of human small RNAs in vitro and in frog oocytes
Effect of 3′ terminal adenylic acid residue on the uridylation of human small RNAs in vitro and in frog oocytes
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DOI：
10.1017/s1355838200000285
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发表时间：
2000-09-01
期刊：
影响因子：
4.5
通讯作者：
Reddy, R
中科院分区：
文献类型：
--
作者：
Chen, YH;Sinha, K;Reddy, R
已知几种小RNA包括人和非洲爪蟾的信号识别颗粒（SRP）RNA、U2小核RNA（snRNA）和7SK RNA在转录后被腺苷酸化，而U6 snRNA和核糖体5S RNA在转录后被3'端尿苷酸化。我们提供的证据表明，一小部分来自人类和非洲爪蟾卵母细胞的U6 snRNA和5S核糖体RNA分子在其转录后含有一个单独的腺苷酸残基。3'端。这些数据表明，U6 snRNA和5S rRNA在其3'端通过尿苷酸化和腺苷酸化进行转录后修饰。尽管3'端带有尿苷酸残基的SRP RNA、7SK RNA、5S RNA和U6 snRNA容易被尿苷化，但所有这些3'端带有转录后添加的腺苷酸残基的RNA在体外都没有被尿苷化，或者当将带有3' A（OH）的U6 snRNA注射到爪蟾卵母细胞中时，这些结果表明，在SRP RNA、U6 snRNA、5S rRNA或75K RNA的3'端存在单个转录后添加的腺苷酸残基阻止了3'尿苷化。这些数据还表明，腺苷酸化和尿苷酸化是在一些小RNA的3'端添加核苷酸的两个竞争过程，并表明3'腺苷酸化的功能之一可能是负面影响小RNA的3'尿苷酸化。
It is known that several small RNAs including human and Xenopus signal recognition particle (SRP) RNA, U2 small nuclear RNA (snRNA) and 7SK RNAs are posttranscriptionally adenylated, whereas U6 sn RNA and ribosomal 5S RNA are posttranscriptionally uridylated on their 3' ends, In this study, we provide evidence that a small fraction of U6 snRNA and 5S ribosomal RNA molecules from human as well as Xenopus oocytes contain a single posttranscriptionally added adenylic acid residue on their 3' ends. These data show that U6 snRNA and 5S rRNAs are posttranscriptionally modified on their 3' ends by both uridylation and adenylation. Although the SRP RNA, 7SK RNA, 5S RNA, and U6 snRNA with the uridylic acid residue on their 3' ends were readily uridylated, all these RNAs with posttranscriptionally added adenylic acid residue on their 3' ends were not uridylated in vitro, or when U6 snRNA with 3' A(OH) was injected into Xenopus oocytes, These results show that the presence of a single posttranscriptionally added adenylic acid residue on the 3' end of SRP RNA, U6 snRNA, 5S rRNA, or 75K RNA prevents 3' uridylation. These data also show that adenylation and uridylation are two competing processes that add nucleotides on the 3' end of some small RNAs and suggest that one of the functions of the 3' adenylation may be to negatively affect the 3' uridylation of small RNAs.