A Novel Small-Subunit Processome Assembly Intermediate That Contains the U3 snoRNP, Nucleolin, RRP5, and DBP4
A Novel Small-Subunit Processome Assembly Intermediate That Contains the U3 snoRNP, Nucleolin, RRP5, and DBP4
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一种新型小亚基加工组组装中间体，包含 U3 snoRNP、核仁素、RRP5 和 DBP4
DOI：
10.1128/mcb.00029-09
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发表时间：
2009
影响因子：
5.3
通讯作者：
N. Watkins
中科院分区：
文献类型：
--
作者：
A. Turner;A. Knox;J. Prieto;B. McStay;N. Watkins
真核生物的18 SrRNA加工是由小亚基（SSU）加工体介导的，SSU是由U3小核仁RNP（U3 snoRNP）、tUTP、bUTP、MPP 10和BMS 1/RCL 1亚复合物组成的加工机器。我们报告说，人类SSU处理体是一个动态的结构，在核糖体生物合成的早期阶段发生的招募和释放的亚复合物。当前rRNA转录被阻断或tUTP蛋白被耗尽时，一种新的50 S U3 snoRNP积累。该复合物不含tUTP、bUTP、MPP 10和BMS 1/RCL 1亚复合物，但与RNA结合蛋白核仁素和RRP 5以及RNA解旋酶DBP 4相关。我们的数据表明，50 S U3 snoRNP是一种SSU组装中间体，可能通过RNA结合蛋白核仁素和RRP 5被招募到前rRNA。我们预测，核仁素只是短暂地与SSU加工体，并可能离开复杂的50 S U3 snoRNP招聘后不久。核仁素结合位点可能与其他几个关键因素重叠，我们认为这种蛋白质必须离开SSU加工体才能进行前rRNA加工。
ABSTRACT Eukaryotic 18S rRNA processing is mediated by the small subunit (SSU) processome, a machine comprised of the U3 small nucleolar RNP (U3 snoRNP), tUTP, bUTP, MPP10, and BMS1/RCL1 subcomplexes. We report that the human SSU processome is a dynamic structure with the recruitment and release of subcomplexes occurring during the early stages of ribosome biogenesis. A novel 50S U3 snoRNP accumulated when either pre-rRNA transcription was blocked or the tUTP proteins were depleted. This complex did not contain the tUTP, bUTP, MPP10, and BMS1/RCL1 subcomplexes but was associated with the RNA-binding proteins nucleolin and RRP5 and the RNA helicase DBP4. Our data suggest that the 50S U3 snoRNP is an SSU assembly intermediate that is likely recruited to the pre-rRNA through the RNA-binding proteins nucleolin and RRP5. We predict that nucleolin is only transiently associated with the SSU processome and likely leaves the complex not long after 50S U3 snoRNP recruitment. The nucleolin-binding site potentially overlaps that of several other key factors, and we propose that this protein must leave the SSU processome for pre-rRNA processing to occur.
影响因子：
14.9
作者：
Granneman, S;Gallagher, JEG;Pruijn, GJM
通讯作者：
Pruijn, GJM
Mpp10p 关联需要 U3 snoRNA 的一个意想不到的保守元件。
DOI：
10.1017/s1355838201010238
发表时间：
2001
期刊：
RNA (New York, N.Y.)
影响因子：
--
作者：
Wormsley,S;Samarsky,DA;Fournier,MJ;Baserga,SJ
通讯作者：
Baserga,SJ
影响因子：
10.5
作者：
Gallagher, JEG;Dunbar, DA;Baserga, SJ
通讯作者：
Baserga, SJ