Spatial regulation of the KH domain RNA-binding protein Rnc1 mediated by a Crm1-independent nuclear export system in Schizosaccharomyces pombe.
Spatial regulation of the KH domain RNA-binding protein Rnc1 mediated by a Crm1-independent nuclear export system in Schizosaccharomyces pombe.
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粟酒裂殖酵母中独立于 Crm1 的核输出系统介导的 KH 结构域 RNA 结合蛋白 Rnc1 的空间调节。
DOI：
10.1111/mmi.13636
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Sugiura R.
中科院分区：
文献类型：
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作者：
Satoh R;Matsumura Y;Tanaka A;Takada M;Ito Y;Hagihara K;Inari M;Kita A;Fukao A;Fujiwara T;Hirai S;Tani T;Sugiura R.
RNA结合蛋白（RBP）在基因表达的转录后调控中起着重要作用，包括mRNA的稳定性，转运和翻译。裂殖酵母nc 1+编码K同源（KH）-型RBP，其结合并稳定Pmp 1 MAPK磷酸酶mRNA，从而抑制钙调磷酸酶缺失和MAPK信号转导突变体的Cl-超敏性。在这里，我们分析了Rnc 1的空间调控，并发现了一个假定的核输出信号（内斯）Rnc 1，它决定了Rnc 1的细胞质定位在一个Crm 1-独立的方式。值得注意的是，NESRnc 1突变改变了Rnc 1的核质分布，并消除了其抑制钙调磷酸酶缺失的功能，尽管Rnc 1内斯突变体保持了结合Pmp 1 mRNA的能力。有趣的是，Rnc 1内斯突变体使Pmp 1 mRNA不稳定，表明Rnc 1细胞质定位的功能重要性。Rae 1的突变，而不是Mex 67的缺失或过度生产，诱导Rnc 1在细胞核中的积累，表明Rnc 1从细胞核出口到细胞质通过mRNA出口途径涉及Rae 1。重要的是，Rnc 1 KH-结构域的突变消除了mRNA结合能力并诱导了核定位，这表明Rnc 1可能与其靶mRNA一起从核中输出。总的来说，功能性Rae 1依赖的mRNA输出系统可能会影响Rnc 1的细胞质定位和功能。
RNA‐binding proteins (RBPs) play important roles in the posttranscriptional regulation of gene expression, including mRNA stability, transport and translation. Fission yeastrnc1+encodes a K Homology (KH)‐type RBP, which binds and stabilizes the Pmp1 MAPK phosphatase mRNA thereby suppressing the Cl−hypersensitivity of calcineurin deletion and MAPK signaling mutants. Here, we analyzed the spatial regulation of Rnc1 and discovered a putative nuclear export signal (NES)Rnc1, which dictates the cytoplasmic localization of Rnc1 in a Crm1‐independent manner. Notably, mutations in the NESRnc1altered nucleocytoplasmic distribution of Rnc1 and abolished its function to suppress calcineurin deletion, although the Rnc1 NES mutant maintains the ability to bind Pmp1 mRNA. Intriguingly, the Rnc1 NES mutant destabilized Pmp1 mRNA, suggesting the functional importance of the Rnc1 cytoplasmic localization. Mutation in Rae1, but not Mex67 deletion or overproduction, induced Rnc1 accumulation in the nucleus, suggesting that Rnc1 is exported from the nucleus to the cytoplasm via the mRNA export pathway involving Rae1. Importantly, mutations in the Rnc1 KH‐domains abolished the mRNA‐binding ability and induced nuclear localization, suggesting that Rnc1 may be exported from the nucleus together with its target mRNAs. Collectively, the functional Rae1‐dependent mRNA export system may influence the cytoplasmic localization and function of Rnc1.