Flexibility of interdomain contacts revealed by topological isomers of bivalent consolidated ligands to the dual Src homology domain SH(32) of abelson.
Flexibility of interdomain contacts revealed by topological isomers of bivalent consolidated ligands to the dual Src homology domain SH(32) of abelson.
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DOI：
10.1021/bi982744j
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发表时间：
1999-03
期刊：
影响因子：
2.9
通讯作者：
Q. Xu;J. Zheng;R. Xu;G. Barany;D. Cowburn
中科院分区：
文献类型：
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作者：
Q. Xu;J. Zheng;R. Xu;G. Barany;D. Cowburn
Src同源（SH）2和SH 3结构域存在于多种参与细胞信号传导和结构控制的蛋白质中。域之间可能的相互关系不容易调查，即使多个域包含结构的几种情况下已经研究了结构。作为对直接结构方法的补充，我们已经开发了整合的配体并测试了它们与Abl SH（32）复合物的结合。整合的配体联合收割机在相同的分子中结合由SH 2和SH 3结构域识别的肽序列，即，分别为Pro-Val-pTyr-Glu-Asn-Val和Pro-Pro-Ala-Tyr-Pro-Pro-Pro-Val-Pro;这些通过寡甘氨酰接头连接。四种类型的配体的化学合成，代表所有可能的相对取向的配体。发现它们的亲和力随结合部分拓扑结构和接头长度而变化。这些类型中的两种显示出以高亲和力和特异性结合SH 2和SH 3双重结构域，与最强结合的单价等价物相比，显示出一个数量级的增加。这些结果表明，在Abl SH（32）中SH 2和SH 3的相对取向不是固定的，并且这种合成方法通常可用于确定连接的复合物的结构和用于开发具有高亲和力和特异性的试剂。
Src homology (SH)2 and SH3 domains are found in a variety of proteins involved in the control of cellular signaling and architecture. The possible interrelationships between domains are not easily investigated, even though several cases of multiple domain-containing constructs have been studied structurally. As a complement to direct structural methods, we have developed consolidated ligands and tested their binding to the Abl SH(32) complex. Consolidated ligands combine in the same molecule peptide sequences recognized by SH2 and SH3 domains, i.e., Pro-Val-pTyr-Glu-Asn-Val and Pro-Pro-Ala-Tyr-Pro-Pro-Pro-Pro-Val-Pro, respectively; these are joined by oligoglycyl linkers. Four types of ligands were chemically synthesized, representing all the possible relative orientations of ligands. Their affinities were found to vary with binding portion topologies and linker lengths. Two of these types were shown to bind to both SH2 and SH3 dual domains with high affinities and specificities, showing increases of one order of magnitude, as compared to the most strongly bound monovalent equivalent. These results suggest that the relative orientation of SH2 and SH3 in Abl SH(32) is not fixed, and this synthetic approach may be generally useful for determining the structures of ligated complexes and for developing reagents with high affinities and specificities.