PROTEIN-MEDIATED NUCLEAR EXPORT OF RNA - 5S RIBOSOMAL-RNA CONTAINING SMALL RNPS IN XENOPUS OOCYTES
PROTEIN-MEDIATED NUCLEAR EXPORT OF RNA - 5S RIBOSOMAL-RNA CONTAINING SMALL RNPS IN XENOPUS OOCYTES
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DOI：
10.1016/0092-8674(90)90665-2
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发表时间：
1990-02-23
期刊：
影响因子：
64.5
通讯作者：
PIELER, T
中科院分区：
文献类型：
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作者：
GUDDAT, U;BAKKEN, AH;PIELER, T
我们分析了非洲爪蟾卵母细胞中显微注射基因转录的5S RNA和5S变体的RNP形成和核质迁移。使用抗血清对三种不同的蛋白质，我们发现，新转录的核5S rRNA瞬时与La抗原相互作用。然后La蛋白被核糖体蛋白L5或5S基因特异性转录因子IIIA（TFIIIA）取代，并且这两种RNP中的每一种都迁移出细胞核并积累在细胞质中。与L5和TFIIIA相互作用能力受损的RNA分子保留在细胞核中。因此，L5和TFIIIA定义了一种新的参与RNA核输出的蛋白质功能类别。此外，我们表明，RNP迁移耗尽TFIIIA的细胞核，导致新注入的5S rRNA基因的转录能力的损失。
We have analyzed RNP formation and nucleocytoplasmic migration of 5S RNA and 5S variants transcribed from microinjected genes in Xenopus oocytes. Using antisera against three different proteins we find that newly transcribed nuclear 5S rRNA transiently interacts with La antigen. The La protein in then replaced by either ribosomal protein L5 or the 5S gene-specific transcription factor IIIA (TFIIIA), and each of these two RNPs migrates out of the nucleus and accumulates in the cytoplasm. RNA molecules that are impaired in their ability to interact with L5 and TFIIIA are retained in the nucleus. Thus, L5 and TFIIIA define a new functional class of proteins involved in the nuclear export of RNA. In addition, we show that RNP migration depletes the nucleus of TFIIIA, resulting in a loss of transcription competence for newly injected 5S rRNA genes.