All three functional domains of the large ribosomal subunit protein L25 are required for both early and late pre-rRNA processing steps in Saccharomyces cerevisiae.
All three functional domains of the large ribosomal subunit protein L25 are required for both early and late pre-rRNA processing steps in Saccharomyces cerevisiae.
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大核糖体亚基蛋白 L25 的所有三个功能域都是酿酒酵母早期和晚期 pre-rRNA 加工步骤所必需的。
作者：
C. Beekvelt;Muriel de Graaff;Alex W. Faber;J. Riet;Jaap Venema;H. A. Raué
突变分析表明，参与核糖体蛋白L25结合的25 S rRNA结构域III中区域的完整性对于酵母酿酒酵母中成熟25 S rRNA的产生是必不可少的。然而，即使是不明显影响L25识别的结构改变，如通过体外测定所测量的，也通过抑制ITS 2从27 S（B）前体的去除而强烈减少25 S rRNA的形成。为了进一步分析L25在酵母pre-rRNA加工中的作用，我们研究了蛋白质的遗传耗竭或其三个先前鉴定的功能结构域中的每一个的突变的影响，所述功能结构域分别涉及核输入（N-末端）、RNA结合（中央）和60 S亚基组装（C-末端）。缺失L25或突变其（前）rRNA结合结构域阻断了27 S（B）前体向5.8S/25 S rRNA的转化，证实了L25的组装对于ITS 2加工是必需的。然而，在L25的N-或C-末端结构域中的突变，仅略微影响其与（前）rRNA结合的能力，也导致ITS 2加工缺陷。此外，在所有情况下，在早期切割位点A0、A1和A2处的加工效率显著降低。我们的结论是，L25的组装是必要的，但不足以去除ITS 2，以及在早期站点完全有效的切割。位于L25的N-和C-末端结构域中的额外元件对于前rRNA加工的两个方面都是必需的。
Mutational analysis has shown that the integrity of the region in domain III of 25S rRNA that is involved in binding of ribosomal protein L25 is essential for the production of mature 25S rRNA in the yeast Saccharomyces cerevisiae. However, even structural alterations that do not noticeably affect recognition by L25, as measured by an in vitro assay, strongly reduced 25S rRNA formation by inhibiting the removal of ITS2 from the 27S(B) precursor. In order to analyze the role of L25 in yeast pre-rRNA processing further we studied the effect of genetic depletion of the protein or mutation of each of its three previously identified functional domains, involved in nuclear import (N-terminal), RNA binding (central) and 60S subunit assembly (C-terminal), respectively. Depletion of L25 or mutating its (pre-)rRNA-binding domain blocked conversion of the 27S(B) precursor to 5.8S/25S rRNA, confirming that assembly of L25 is essential for ITS2 processing. However, mutations in either the N- or the C-terminal domain of L25, which only marginally affect its ability to bind to (pre-)rRNA, also resulted in defective ITS2 processing. Furthermore, in all cases there was a notable reduction in the efficiency of processing at the early cleavage sites A0, A1 and A2. We conclude that the assembly of L25 is necessary but not sufficient for removal of ITS2, as well as for fully efficient cleavage at the early sites. Additional elements located in the N- as well as C-terminal domains of L25 are required for both aspects of pre-rRNA processing.
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核糖体蛋白 S6、S8、S15 和 S18 与 16 S 核糖体 RNA 中心结构域的相互作用。
影响因子：
5.6
作者：
Svensson,P;Changchien,LM;Craven,GR;Noller,HF
通讯作者：
Noller,HF
DOI：
10.1073/pnas.94.7.2864
发表时间：
1997-04-01
影响因子：
11.1
作者：
Liang, WQ;Fournier, MJ
通讯作者：
Fournier, MJ
影响因子：
5.6
作者：
POWERS, T;CHANGCHIEN, LM;NOLLER, HF
通讯作者：
NOLLER, HF
通过酵母核膜的体外易位。
DOI：
--
发表时间：
1989
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Kalinich,JF;Douglas,MG
通讯作者：
Douglas,MG