Export and transport of tRNA are coupled to a multi-protein complex
Export and transport of tRNA are coupled to a multi-protein complex
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DOI：
10.1042/0264-6021:3460107
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发表时间：
2000-02-15
影响因子：
4.1
通讯作者：
Müller, PK
中科院分区：
文献类型：
--
作者：
Kruse, C;Willkomm, DK;Müller, PK
Vigilin是一种普遍存在的多异质核核糖核蛋白（hnRNP） K同源（KH）结构域蛋白。在这里，我们证明纯化的重组人vigilin结合tRNA分子具有高亲和力，尽管具有有限的特异性。核显微注射实验首次揭示了免疫亲和纯化的核vigilin核心复合物（VCCN）和重组vigilin加速tRNA从人细胞的细胞核输出。核tRNA受体输出-t是VCCN的一部分。延伸系数（EF）富含VCCN及其细胞质对应体VCCC，而EF-1 β、EF-1 γ和EF-1 δ基本局限于VCCC。我们的研究结果进一步表明，vigilin和export -t可能在tRNA输出过程中相互作用，提供了通道tRNA周期已经在细胞核内启动的证据，并说明细胞内tRNA运输与含有tRNA的细胞质多蛋白复合物组成的离散变化有关。
Vigilin is a ubiquitous multi heterogeneous nuclear ribonucleoprotein (hnRNP) K homologous (KH)-domain protein. Here we demonstrate that purified recombinant human vigilin binds tRNA molecules with high affinity, although with limited specificity. Nuclear microinjection experiments revealed for the first time that the immuno-affinity-purified nuclear vigilin core complex (VCCN) as well as recombinant vigilin accelerate tRNA export from the nucleus in human cells. The nuclear tRNA receptor exportin-t is part of the VCCN. Elongation factor (EF)Icc. is enriched in VCCN and its cytoplasmic counterpart VCCC, whereas EF-1 beta, EF-1 gamma and EF-1 delta are basically confined to the VCCC. Our results suggest further that vigilin and exportin-t might interact during tRNA export, provide evidence that the channeled tRNA cycle is already initiated in the nucleus, and illustrate that intracellular tRNA trafficking is associated with discrete changes in the composition of cellular cytoplasmic multiprotein complexes containing tRNA.