Poly(A)-binding proteins: multifunctional scaffolds for the post-transcriptional control of gene expression.
Poly(A)-binding proteins: multifunctional scaffolds for the post-transcriptional control of gene expression.
复制标题
poly（a）结合蛋白：用于基因表达的转录后控制的多功能支架。
DOI：
10.1186/gb-2003-4-7-223
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发表时间：
2003
期刊：
影响因子：
12.3
通讯作者：
Jacobson, Allan
中科院分区：
文献类型：
--
作者：
Mangus, David A;Evans, Matthew C;Jacobson, Allan
聚(A)结合蛋白（PABPs）是高度保守的多肽，与mrna的聚(A)尾部结合。虽然它们缺乏催化活性，但PABPs具有多种作用，包括调节poly(A)尾部的长度，调节mRNA从细胞核的输出，翻译起始和终止，核糖体的再循环以及mRNA的稳定性。大多数真核mrna都受到转录后修饰的影响，包括盖帽、剪接和聚腺苷化。聚腺苷化过程增加了一个3'聚(a)尾部，并为mRNA提供了一个结合位点，以结合一类主要的调节因子，即聚(a)结合蛋白（PABPs）。这些高度保守的多肽只存在于真核生物中；单细胞真核生物每个都有一个PABP，而人类有五个，拟南芥有八个。它们通常使用一个或多个rna识别基序结合poly(A)，这些基序与许多其他真核rna结合蛋白共同的球状结构域。虽然它们缺乏催化活性，但PABPs在介导基因表达方面具有多种作用。核PABPs对于poly(A)尾部的合成、调节其最终长度和刺激mRNA的成熟是必需的。与PABP的关联也是一些mrna从细胞核输出的必要条件。在细胞质中，PABP促进信使核糖核蛋白颗粒“闭环”结构的形成，这对于促进翻译起始和终止、核糖体再循环和mRNA稳定性的额外PABP活性至关重要。总的来说，这些连续的核和细胞质贡献构成了一个循环，在这个循环中，PABPs和聚(a)尾部首先创建然后消除控制mRNA功能的顺式相互作用网络。
The poly(A)-binding proteins (PABPs) are highly conserved polypeptides that bind to poly(A) tails of mRNAs. Although they lack catalytic activity, PABPs have several roles, including actions in regulating the length of the poly(A) tail, in regulating the export of mRNAs from the nucleus, in translation initiation and termination, in recycling of ribosomes, and in mRNA stability. Most eukaryotic mRNAs are subject to considerable post-transcriptional modification, including capping, splicing, and polyadenylation. The process of polyadenylation adds a 3' poly(A) tail and provides the mRNA with a binding site for a major class of regulatory factors, the poly(A)-binding proteins (PABPs). These highly conserved polypeptides are found only in eukaryotes; single-celled eukaryotes each have a single PABP, whereas humans have five and Arabidopis has eight. They typically bind poly(A) using one or more RNA-recognition motifs, globular domains common to numerous other eukaryotic RNA-binding proteins. Although they lack catalytic activity, PABPs have several roles in mediating gene expression. Nuclear PABPs are necessary for the synthesis of the poly(A) tail, regulating its ultimate length and stimulating maturation of the mRNA. Association with PABP is also a requirement for some mRNAs to be exported from the nucleus. In the cytoplasm, PABPs facilitate the formation of the 'closed loop' structure of the messenger ribonucleoprotein particle that is crucial for additional PABP activities that promote translation initiation and termination, recycling of ribosomes, and stability of the mRNA. Collectively, these sequential nuclear and cytoplasmic contributions comprise a cycle in which PABPs and the poly(A) tail first create and then eliminate a network of cis- acting interactions that control mRNA function.