An unexpected, conserved element of the U3 snoRNA is required for Mpp10p association.
An unexpected, conserved element of the U3 snoRNA is required for Mpp10p association.
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Mpp10p 关联需要 U3 snoRNA 的一个意想不到的保守元件。
DOI：
10.1017/s1355838201010238
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
Baserga,SJ
中科院分区：
文献类型：
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作者：
Wormsley,S;Samarsky,DA;Fournier,MJ;Baserga,SJ
U3小核仁核糖核蛋白（snoRNP）由一个小核仁RNA（snoRNA）和至少10种蛋白质组成。U3 snoRNA与pre-rRNA碱基配对，进行A0、A1和A2加工反应，导致18 S rRNA从新生的pre-rRNA转录物中释放。酵母U3 snoRNA可分为一个短的5′结构域（nt 1-39）和一个较大的3′结构域（nt 73到3′端），它们被一段称为铰链区的核苷酸（nt 40-72）分开。前rRNA碱基配对所需的序列存在于5′结构域和铰链区，而3′结构域大部分被蛋白质覆盖。Mpp 10 p是U3 snoRNP特有的蛋白质组分之一，在A1和A2位点的加工中发挥作用。由于其在U3 snoRNP功能中的关键作用，我们确定了U3 snoRNA中的哪些序列是Mpp 10 p结合所需的。与原纤蛋白和以前以这种方式研究的所有U3 snoRNP组分不同，3′结构域中的序列不足以与Mpp 10 p结合。相反，需要U3 snoRNA铰链区中的保守序列元件，将Mpp 10 p放置在U3 snoRNP功能中心中进行前rRNA碱基配对相互作用的5′结构域附近。
The U3 small nucleolar ribonucleoprotein (snoRNP) is composed of a small nucleolar RNA (snoRNA) and at least 10 proteins. The U3 snoRNA base pairs with the pre-rRNA to carry out the A0, A1, and A2 processing reactions that lead to the release of the 18S rRNA from the nascent pre-rRNA transcript. The yeast U3 snoRNA can be divided into a short 5′ domain (nt 1–39) and a larger 3′ domain (73 to the 3′ end) separated by a stretch of nucleotides called the hinge region (nt 40–72). The sequences required for pre-rRNA base pairing are found in the 5′ domain and hinge region whereas the 3′ domain is largely covered with proteins. Mpp10p, one of the protein components unique to the U3 snoRNP, plays a role in processing at the A1 and A2 sites. Because of its critical role in U3 snoRNP function, we determined which sequences in the U3 snoRNA are required for Mpp10p association. Unlike fibrillarin and all the previous U3 snoRNP components studied in this manner, sequences in the 3′ domain are not sufficient for Mpp10p association. Instead, a conserved sequence element in the U3 snoRNA hinge region is required, placing Mpp10p near the 5′ domain that carries out the pre-rRNA base-pairing interactions in the functional center of the U3 snoRNP.