The C-terminal domain of pol II and a DRB-sensitive kinase are required for 3′ processing of U2 snRNA
The C-terminal domain of pol II and a DRB-sensitive kinase are required for 3′ processing of U2 snRNA
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DOI：
10.1093/emboj/cdg077
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发表时间：
2003-02-17
期刊：
影响因子：
11.4
通讯作者：
Murphy, S
中科院分区：
文献类型：
--
作者：
Medlin, JE;Uguen, P;Murphy, S
由RNA聚合酶II转录的人类snRNA基因（如U1和U2）具有一个特征性的TATA-less启动子，包含一个必需的近端序列元件。这些非聚腺苷化rna的3‘端形成需要一个特殊的3’盒元件，其功能是启动子特异性的。在这里，我们发现截断RNA聚合酶II的c端结构域（CTD），并用CTD激酶抑制剂(包括DRB（5,6-二氯-1- β -d -核糖呋喃基苯并咪唑）处理细胞，导致U2转录本适当的3'端形成急剧减少。磷酸化的CTD激活3' box识别与磷酸化CTD在mRNA加工中的作用是一致的。然而，CTD激酶抑制剂对U2基因的转录起始或转录延伸影响不大，而β -肌动蛋白基因的转录延伸受到严重影响。这一结果突出了snRNA和mRNA基因转录的差异。
The human snRNA genes transcribed by RNA polymerase II (e.g. U1 and U2) have a characteristic TATA-less promoter containing an essential proximal sequence element. Formation of the 3' end of these non-polyadenylated RNAs requires a specialized 3' box element whose function is promoter specific. Here we show that truncation of the C-terminal domain (CTD) of RNA polymerase II and treatment of cells with CTD kinase inhibitors, including DRB (5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole), causes a dramatic reduction in proper 3' end formation of U2 transcripts. Activation of 3' box recognition by the phosphorylated CTD would be consistent with the role of phospho-CTD in mRNA processing. CTD kinase inhibitors, however, have little effect on initiation or elongation of transcription of the U2 genes, whereas elongation of transcription of the beta-actin gene is severely affected. This result highlights differences in transcription of snRNA and mRNA genes.