Post-transcriptional regulation of gene expression is largely achieved at the level of splicing in the nucleus, and translation and mRNA decay in the cytosol. While the regulation may be global, through the direct inhibition of central factors, such as the spliceosome, translation initiation factors and mRNA decay enzymes, in many instances transcripts bearing specific sequences or particular features are regulated by RNA-binding factors which mobilize or impede recruitment of these machineries. This review focuses on the Pat1 family of RNA-binding proteins, conserved from yeast to man, that enhance the removal of the 5' cap by the decapping enzyme Dcp1/2, leading to mRNA decay and also have roles in translational repression. Like Dcp1/2, other decapping coactivators, including DDX6 and Edc3, and translational repressor proteins, Pat1 proteins are enriched in cytoplasmic P-bodies, which have a principal role in mRNA storage. They also concentrate in nuclear Cajal-bodies and splicing speckles and in man, impact splice site choice in some pre-mRNAs. Pivotal to these functions is the association of Pat1 proteins with distinct heptameric Lsm complexes: the cytosolic Pat1/Lsm1-7 complex mediates mRNA decay and the nuclear Pat1/Lsm2-8 complex alternative splicing. This dual role of human Pat1b illustrates the power of paralogous complexes to impact distinct processes in separate compartments. The review highlights our recent findings that Pat1b mediates the decay of AU-rich mRNAs, which are particularly enriched in P-bodies, unlike the decapping activator DDX6, which acts on GC-rich mRNAs, that tend to be excluded from P-bodies, and discuss the implications for mRNA decay pathways. This article is categorized under: RNA Turnover and Surveillance > Regulation of RNA Stability RNRNA Processing > Splicing Regulation/Alternative Splicing Translation > Translation Regulation.

中文翻译：

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Pat1 RNA结合蛋白：多任务穿梭蛋白。

基因表达的转录后调节主要在细胞核的剪接水平以及细胞质中的翻译和mRNA降解水平实现。尽管调节可能是全球性的，但通过直接抑制诸如剪接体，翻译起始因子和mRNA衰减酶等中枢因子，在许多情况下，带有特定序列或特定特征的转录本受动员或阻碍募集的RNA结合因子调节。这些机器。这篇综述的重点是从酵母到人保守的RNA结合蛋白的Pat1家族，该家族增强了脱盖酶Dcp1 / 2对5'帽的去除，导致mRNA衰变，并且在翻译抑制中也起作用。像Dcp1 / 2一样，其他包括DEX6和Edc3在内的去盖蛋白共激活因子以及翻译阻遏蛋白，Pat1蛋白富含细胞质P体，其在mRNA存储中起主要作用。他们还专注于核Cajal体和剪接斑点，在人中还影响某些前mRNA的剪接位点选择。这些功能的关键是Pat1蛋白与不同的七聚体Lsm复合体的关联：胞质Pat1 / Lsm1-7复合体介导mRNA的衰变和核Pat1 / Lsm2-8复合体的选择性剪接。人类Pat1b的双重作用说明了同源复合物影响单独隔室中不同过程的能力。该评论突显了我们最近的发现，即Pat1b介导了富含AU的mRNA的衰变，尤其是在P体内富集，而去盖活化剂DDX6却对富含GC的mRNA起作用，而后者往往被排除在P体内，并讨论对mRNA衰变途径的影响。本文归类于：RNA周转和监视> RNA稳定性RNRNA处理的调控>剪接调控/替代剪接翻译>翻译调控。