DEPLETION OF U3 SMALL NUCLEOLAR RNA INHIBITS CLEAVAGE IN THE 5' EXTERNAL TRANSCRIBED SPACER OF YEAST PRE-RIBOSOMAL RNA AND IMPAIRS FORMATION OF 18S RIBOSOMAL-RNA
DEPLETION OF U3 SMALL NUCLEOLAR RNA INHIBITS CLEAVAGE IN THE 5' EXTERNAL TRANSCRIBED SPACER OF YEAST PRE-RIBOSOMAL RNA AND IMPAIRS FORMATION OF 18S RIBOSOMAL-RNA
复制标题
DOI：
10.1002/j.1460-2075.1991.tb05001.x
复制
发表时间：
1991-12-01
期刊：
影响因子：
11.4
通讯作者：
ARES, M
中科院分区：
文献类型：
--
作者：
HUGHES, JMX;ARES, M
将单个真核前核糖体RNA(Pre-rRNA)转化为成熟的18S(小亚基)、5.8S和25-28S(大亚基)rRNA需要多个加工事件。我们曾经问过，通过有条件地抑制U3的合成来耗尽U3的酿酒酵母，是否需要U3小核仁RNA来处理体内的前rRNA。由此产生的特定前rRNA的积累和耗尽模式表明，U3是导致18S rRNA成熟的多个事件所必需的。这些包括5‘外部转录间隔区内的初始切割，类似于哺乳动物Pre-rRNA的U3依赖的初始处理事件。大亚基rRNA的形成不受U3耗尽的影响。U3耗竭和U14小核仁RNA耗尽与核仁蛋白原纤维蛋白(NOP1)的作用相似，表明这些可能是单个高度保守的加工复合体的组成部分。
Multiple processing events are required to convert a single eukaryotic pre-ribosomal RNA (pre-rRNA) into mature 18S (small subunit), 5.8S and 25-28S (large subunit) rRNAs. We have asked whether U3 small nucleolar RNA is required for pre-rRNA processing in vivo by depleting Saccharomyces cerevisiae of U3 by conditional repression of U3 synthesis. The resulting pattern of accumulation and depletion of specific pre-rRNAs indicates that U3 is required for multiple events leading to the maturation of 18S rRNA. These include an initial cleavage within the 5' external transcribed spacer, resembling the U3 dependent initial processing event of mammalian pre-rRNA. Formation of large subunit rRNAs is unaffected by U3 depletion. The similarity between the effects of U3 depletion and depletion of U14 small nucleolar RNA and the nucleolar protein fibrillarin (NOP1) suggests that these could be components of a single highly conserved processing complex.