Functional modules in ribosomal protein L5 for ribonucleoprotein complex formation and nucleocytoplasmic transport
Functional modules in ribosomal protein L5 for ribonucleoprotein complex formation and nucleocytoplasmic transport
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DOI：
10.1074/jbc.274.48.33951
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发表时间：
1999-11-26
影响因子：
4.8
通讯作者：
Pieler, T
中科院分区：
文献类型：
--
作者：
Claussen, M;Rudt, F;Pieler, T
核糖体蛋白L5形成一个小的，外的，带有5 s核糖体RNA，称为5 s核糖核蛋白复合物，在核蛋白中，核蛋白质中的核细胞中的核和细胞质之间穿梭，在L5中映射核蛋白的映射元件，介导核蛋白的三种导入的活动（L5分开）（L5分离L5分开）。 - 核定定位序列（NLS）-1，-2和-3），是与全长蛋白相比，RNA结合活性在卵母细胞和体细胞中的功能都涉及L5的N末端和C末端元素，携带L5片段的单个NLS均不能允许在用全长蛋白观察到的核仁。单独的L5-NLS在两个活动方面有所不同。首先，只有L5-NLS-1和-3而非L5-NLS-2，才能促进异源，共价附着的核糖核蛋白蛋白复合物的核转移。其次，只有L5-NLS-1才能与各种不同的进口受体结合。那些识别L5-NLS-2和-3的人尚未确定。
Ribosomal protein L5 forms a small, extraribosomal complex with 5 S ribosomal RNA, referred to as the 5 S ribonucleoprotein complex, which shuttles between nucleus and cytoplasm in Xenopus oocytes, Mapping elements in L5 that mediate nuclear protein import defines three separate such activities (L5-nuclear localization sequence (NLS)-1, -2, and -3), which are functional in both oocytes and somatic cells, RNA binding activity involves N-terminal as well as C-terminal elements of L5, In contrast to the full length protein, none of the individual NLSs carrying L5 fragments are able to allow for the predominating accumulation in the nucleoli that is observed with the full-length protein. The separate L5-NLSs differ in respect to two activities. Firstly, only L5-NLS-1 and -3, not L5-NLS-2, are capable of promoting the nuclear transfer of a heterologous, covalently attached ribonucleoprotein complex. Secondly, only L5-NLS-1 is able to bind strongly to a variety of different import receptors; those that recognize L5-NLS-2 and -3 have yet to be identified.