Genome-wide prediction and analysis of yeast RNase III-dependent snoRNA processing signals
Genome-wide prediction and analysis of yeast RNase III-dependent snoRNA processing signals
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DOI：
10.1128/mcb.25.8.2981-2994.2005
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发表时间：
2005-04-01
影响因子：
5.3
通讯作者：
Abou Elela, S
中科院分区：
文献类型：
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作者：
Ghazal, G;Ge, DL;Abou Elela, S
在酿酒酵母中，前rRNA和前小核仁RNA(pre-snoRNAs)的成熟涉及共同因素，从而为snoRNA和rRNA合成的共同调控提供了一种潜在的机制。在这项研究中，我们研究了双链RNA特异的RNase Rnt1p对所有已知的snoRNAs成熟的影响。在对Rnt1p裂解信号的电子搜索和对依赖于Rnt1p的表达谱的全基因组分析中，确定了七个新的Rnt1p底物。有趣的是，新发现的两个依赖Rm1p的snoRNAs，SnR39和SnR59，位于核糖体蛋白基因RPL7A和RPL7B的内含子中。体外和体内实验表明，SnR39通常是从RPL7A的套索中加工而来的，这表明RPL7A和SnR39的表达是连锁的。相反，SnR59是通过直接切割RPL7B前-mRNA而产生的，这表明单一的前-mRNA转录本不能被剪接来产生成熟的RPL7B mRNA，并被Rnt1p加工来同时产生成熟的SnR59。这些结果揭示了酵母RNase III在处理内含子编码的snoRNAs过程中的一个新角色，它允许独立调节宿主mRNA及其相关的snoRNA。
In Saccharomyces cerevisiae, the maturation of both pre-rRNA and pre-small nucleolar RNAs (pre-snoRNAs) involves common factors, thereby providing a potential mechanism for the coregulation of snoRNA and rRNA synthesis. In this study, we examined the global impact of the double-stranded-RNA-specific RNase Rnt1p, which is required for pre-rRNA processing, on the maturation of all known snoRNAs. In silico searches for Rnt1p cleavage signals, and genome-wide analysis of the Rnt1p-dependent expression profile, identified seven new Rnt1p substrates. Interestingly, two of the newly identified Rm1p-dependent snoRNAs, snR39 and snR59, are located in the introns of the ribosomal protein genes RPL7A and RPL7B. In vitro and in vivo experiments indicated that snR39 is normally processed from the lariat of RPL7A, suggesting that the expressions of RPL7A and snR39 are linked. In contrast, snR59 is produced by a direct cleavage of the RPL7B pre-mRNA, indicating that a single pre-mRNA transcript cannot be spliced to produce a mature RPL7B mRNA and processed by Rnt1p to produce a mature snR59 simultaneously. The results presented here reveal a new role of yeast RNase III in the processing of intron-encoded snoRNAs that permits independent regulation of the host mRNA and its associated snoRNA.