Accumulation of U14 small nuclear RNA in Saccharomyces cerevisiae requires box C, box D, and a 5', 3' terminal stem.
Accumulation of U14 small nuclear RNA in Saccharomyces cerevisiae requires box C, box D, and a 5', 3' terminal stem.
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U14 小核 RNA 在酿酒酵母中的积累需要盒 C、盒 D 和 5、3 末端茎。
DOI：
10.1128/mcb.12.10.4456-4463.1992
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发表时间：
1992
影响因子：
5.3
通讯作者：
Fournier,MJ
中科院分区：
文献类型：
--
作者：
Huang,GM;Jarmolowski,A;Struck,JC;Fournier,MJ
U14是正常处理rRNA所需的几个核仁小核RNA之一。对酿酒酵母U14的功能定位发现了一些U14积累或功能缺陷的突变体。在这项研究中，我们进一步定义了U14积累所需的三个结构元件。必需元件包括U14保守的box C和box D序列以及5‘，3’末端茎。盒元件在几个核仁小核RNA之间是共同保守的，并与蛋白质纤维蛋白的结合有关。新的突变结果表明，盒C序列UGAUGA的第一个GA碱基是必需的，并且盒D中的两个重要碱基也被鉴定出来。一个致死性的Box C突变体的基因内抑制子已经被分离出来，并表明它含有一个新的Box C类PyGAUG序列，该序列位于正常的Box C上游两个碱基的上游。新的补偿碱基的变化和发现盒元件中的积累缺陷可以通过延伸末端茎来补充，证实了末端茎的重要性。结果表明，观察到的积累缺陷反映了U14的不稳定性，蛋白质与这些元件中的一个或多个结合是代谢稳定所必需的。
U14 is one of several nucleolar small nuclear RNAs required for normal processing of rRNA. Functional mapping of U14 fromSaccharomyces cerevisiaehas yielded a number of mutants defective in U14 accumulation or function. In this study, we have further defined three structural elements required for U14 accumulation. The essential elements include the U14-conserved box C and box D sequences and a 5', 3' terminal stem. The box elements are coconserved among several nucleolar small nuclear RNAs and have been implicated in binding of the protein fibrillarin. New mutational results show that the first GA bases of the box C sequence UGAUGA are essential, and two vital bases in box D have also been identified. An intragenic suppressor of a lethal box C mutant has been isolated and shown to contain a new box C-like PyGAUG sequence two bases upstream of normal box C. The importance of the terminal stem was confirmed from new compensatory base changes and the finding that accumulation defects in the box elements can be complemented by extending the terminal stem. The results suggest that the observed defects in accumulation reflect U14 instability and that protein binding to one or more of these elements is required for metabolic stability.