S1-1/RBM10: Multiplicity and cooperativity of nuclear localisation domains
S1-1/RBM10: Multiplicity and cooperativity of nuclear localisation domains
复制标题
DOI：
10.1111/boc.201200068
复制
发表时间：
2013-04-01
影响因子：
2.7
通讯作者：
Inoue, Akira
中科院分区：
文献类型：
--
作者：
Xiao, Sheng-Jun;Wang, Ling-Yu;Inoue, Akira
背景信息S1-1，也称为RBM 10，是一种由852个残基组成的RNA结合蛋白。其活性的改变导致TARP综合征，这是一种严重的X连锁疾病，在受影响的男性中具有产前或产后致死性。它的分子功能，虽然在很大程度上仍然未知，已被认为是转录和选择性剪接。事实上，S1-1定位于组织细胞和培养细胞的细胞核中。结果经缺失和置换突变，在S1- 1C端第743759位氨基酸处发现一个典型的17个氨基酸的核定位序列（NLS 1）。NLS 1是二分的，其N-末端碱性簇对NLS活性的贡献较弱。S1-1包含两个额外的NLS。其中一个位于aa 60136 RNA识别基序区（NLS 2），另一个位于aa 481540八聚体重复（奥克雷）区（NLS 3）。奥克雷是已知在剪接调节中至关重要的结构域，如RBM 5所示，RBM 5是RBM 10的密切同源物[Bonnal et al.（2008）Mol. Cell 32，8195]。通过表达与EGFP或FLAG标签连接的每个DNA序列来验证NLS活性。这些多个NLS合作，和S1-1成为完全的细胞质后，所有NLS结构域的伴随删除。然而，在某些细胞类型中，S1-1部分是细胞质的，这表明S1-1的细胞定位受到调节。结论S1-1含有多个协同作用的NLS。其中，奥克雷考试是一项迄今未有报道的免入息审查考试。S1-1的核定位似乎在某些情况下受到调节。我们讨论这些NLS的生化过程中，他们参与。
Background information S1-1, also called RBM10, is an RNA-binding protein of 852 residues. An alteration of its activity causes TARP syndrome, a severe X-linked disorder with pre- or post-natal lethality in affected males. Its molecular function, although still largely unknown, has been suggested to be transcription and alternative splicing. In fact, S1-1 localises in the nucleus in tissue cells and cultured cells. Results By deletion and substitution mutagenesis, a classical 17-amino-acid (aa) nuclear localisation sequence (NLS1) was identified at aa 743759 in the C-terminal region of S1-1. NLS1 was bipartite, with its N-terminal basic cluster weakly contributing to the NLS activity. S1-1 contained two additional NLSs. One was in the aa 60136 RNA recognition motif region (NLS2), and the other was a novel NLS motif sequence in the aa 481540 octamer-repeat (OCRE) region (NLS3). The OCRE is a domain known to be critical in splicing regulation, as shown with RBM5, a close homologue of RBM10 [Bonnal et al. (2008) Mol. Cell 32, 8195]. The NLS activities were verified by expressing each DNA sequence linked to EGFP or a FLAG tag. These multiple NLSs acted cooperatively, and S1-1 became completely cytoplasmic after the concomitant removal of all NLS domains. In some cell types, however, S1-1 was partly cytoplasmic, suggesting that cellular localisation of S1-1 is subjected to regulation. Conclusions The present results indicate that S1-1 contains multiple NLSs that act cooperatively. Among them, the OCRE is a hitherto unreported NLS. The nuclear localisation of S1-1 appears to be regulated under certain circumstances. We discuss these NLSs in relation to the biochemical processes they are involved in.