Recognition of polyadenosine RNA by the zinc finger domain of nuclear poly(A) RNA-binding protein 2 (Nab2) is required for correct mRNA 3'-end formation.
Recognition of polyadenosine RNA by the zinc finger domain of nuclear poly(A) RNA-binding protein 2 (Nab2) is required for correct mRNA 3'-end formation.
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DOI：
10.1074/jbc.m110.141127
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发表时间：
2010-08-20
期刊：
影响因子：
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通讯作者：
Corbett AH
中科院分区：
文献类型：
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作者：
Kelly SM;Leung SW;Apponi LH;Bramley AM;Tran EJ;Chekanova JA;Wente SR;Corbett AH
与mRNA转录物的poly（A）尾结合的蛋白质，称为poly（A）结合蛋白（Pabs），在调节RNA稳定性、翻译和核输出中起关键作用。像许多调节转录后加工事件的mRNA结合蛋白一样，将特定功能分配给Pabs是具有挑战性的，因为这些加工事件彼此紧密耦合。为了研究一类新的含锌指的Pabs在这些偶联过程中发挥的作用，我们定义了保守的酿酒酵母Nab 2蛋白的聚腺苷RNA识别模式，并评估了RNA结合中断引起的体内后果。Nab 2的多腺苷RNA识别结构域由三个串联的Cys-Cys-Cys-His（CCCH）锌指组成。表达与聚腺苷RNA结合减少的突变Nab 2蛋白的细胞显示生长缺陷以及聚腺苷酸尾长缺陷，但不在细胞核中积累聚腺苷酸RNA。我们还证明了突变nab 2等位基因和mRNA 3′端加工机制的突变等位基因之间的遗传相互作用。总之，这些数据提供了强有力的证据，即Nab 2与RNA的结合对于正确控制poly（A）尾长至关重要。
Proteins bound to the poly(A) tail of mRNA transcripts, called poly(A)-binding proteins (Pabs), play critical roles in regulating RNA stability, translation, and nuclear export. Like many mRNA-binding proteins that modulate post-transcriptional processing events, assigning specific functions to Pabs is challenging because these processing events are tightly coupled to one another. To investigate the role that a novel class of zinc finger-containing Pabs plays in these coupled processes, we defined the mode of polyadenosine RNA recognition for the conserved Saccharomyces cerevisiae Nab2 protein and assessed in vivo consequences caused by disruption of RNA binding. The polyadenosine RNA recognition domain of Nab2 consists of three tandem Cys-Cys-Cys-His (CCCH) zinc fingers. Cells expressing mutant Nab2 proteins with decreased binding to polyadenosine RNA show growth defects as well as defects in poly(A) tail length but do not accumulate poly(A) RNA in the nucleus. We also demonstrate genetic interactions between mutant nab2 alleles and mutant alleles of the mRNA 3′-end processing machinery. Together, these data provide strong evidence that Nab2 binding to RNA is critical for proper control of poly(A) tail length.