Polypeptide sequences essential for RNA recognition by an enzyme.
Polypeptide sequences essential for RNA recognition by an enzyme.
复制标题
酶识别 RNA 所必需的多肽序列。
DOI：
10.1126/science.2435005
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Schimmel,P
中科院分区：
文献类型：
--
作者：
Regan,L;Bowie,J;Schimmel,P
许多RNA是复杂的球状分子，由类似于蛋白质中发现的二级和三级结构的元件形成。关于蛋白质对RNA的识别知之甚少。在转移RNA（tRNA）的情况下，相当多的证据表明，分散在一维和三维结构的元素是重要的氨酰tRNA合成酶的识别。丙氨酸tRNA合成酶的片段通过体外操作克隆的dalaS基因产生，并检查它们与丙氨酸特异性tRNA的相互作用。识别所必需的序列位于多肽的中间附近，与氨酰腺苷酸合成结构域的羧基末端侧并列。tRNA相互作用强度和特异性的最重要部分取决于少于100个氨基酸的序列。在这个序列中，并在适当的构象的情况下，不超过17个氨基酸的一段负责25%或更多的总合成酶-tRNA的自由能协会。结果提出了一种可能性，即氨酰tRNA合成酶识别特定RNA的一个重要部分涉及相对于蛋白质总大小较短的多肽片段。
Many RNAs are complex, globular molecules formed from elements of secondary and tertiary structure analogous to those found in proteins. Little is known about recognition of RNAs by proteins. In the case of transfer RNAs (tRNAs), considerable evidence suggests that elements dispersed in both the one- and three-dimensional structure are important for recognition by aminoacyl tRNA synthetases. Fragments of alanine tRNA synthetase were created by in vitro manipulations of the clonedalaSgene and examined for their interaction with alanine-specific tRNA. Sequences essential for recognition were located near the middle of the polypeptide, juxtaposed to the carboxyl-terminal side of the domain for aminoacyl adenylate synthesis. The most essential part of the tRNA interaction strength and specificity was dependent on a sequence of fewer than 100 amino acids. Within this sequence, and in the context of the proper conformation, a segment of no more than 17 amino acids was responsible for 25% or more of the total synthetase-tRNA free energy of association. The results raise the possibility that an important part of specific RNA recognition by an aminoacyl tRNA synthetase involves a polypeptide segment that is short relative to the total size of the protein.