The nuclear import of RNA helicase A is mediated by importin-α3
The nuclear import of RNA helicase A is mediated by importin-α3
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DOI：
10.1016/j.bbrc.2005.11.161
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发表时间：
2006-02
影响因子：
3.1
通讯作者：
S. Aratani;T. Oishi;Hidetoshi Fujita;M. Nakazawa;R. Fujii;N. Imamoto;Y. Yoneda;A. Fukamizu;
中科院分区：
文献类型：
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作者：
S. Aratani;T. Oishi;Hidetoshi Fujita;M. Nakazawa;R. Fujii;N. Imamoto;Y. Yoneda;A. Fukamizu;
RNA解旋酶A（RNA helicase A，RHA）是一种ATP酶/解旋酶，在转录激活和RNA加工等多个阶段调控基因表达。已知RHA在细胞核和细胞质之间穿梭。我们鉴定了RHA的核定位信号（NLS），并分析了其核输入机制。RHA的NLS（RHA-NLS）由19个氨基酸残基组成，在物种中高度保守，不具有经典NLS的一致性。体外核输入实验表明，RHA的核输入是Ran依赖的，并通过经典的importin-α/β-依赖途径介导。结合实验表明，RHA-NLS中的碱性残基与importin-α相互作用。此外，RHA-NLS的核输入由输入蛋白-α1支持，并且优先由输入蛋白-α3支持。我们的研究结果表明，RHA的核输入是由importin-α3/importin-β-依赖性途径介导的，并表明importin的特异性可能调节货物蛋白的功能。
RNA helicase A (RHA), an ATPase/helicase, regulates the gene expression at various steps including transcriptional activation and RNA processing. RHA is known to shuttle between the nucleus and cytoplasm. We identified the nuclear localization signal (NLS) of RHA and analyzed the nuclear import mechanisms. The NLS of RHA (RHA-NLS) consisting of 19 amino acid residues is highly conserved through species and does not have the consensus classical NLS. In vitro nuclear import assays revealed that the nuclear import of RHA was Ran-dependent and mediated with the classical importin-α/β-dependent pathway. The binding assay indicated that the basic residues in RHA-NLS were used for interaction with importin-α. Furthermore, the nuclear import of RHA-NLS was supported by importin-α1 and preferentially importin-α3. Our results indicate that the nuclear import of RHA is mediated by the importin-α3/importin-β-dependent pathway and suggest that the specificity for importin may regulate the functions of cargo proteins.