Sowa M E, He W, Slep K C, Kercher M A, Lichtarge O, Wensel T G
Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA.
Nat Struct Biol. 2001 Mar;8(3):234-7. doi: 10.1038/84974.
A critical challenge of structural genomics is to extract functional information from protein structures. We present an example of how this may be accomplished using the Evolutionary Trace (ET) method in the context of the regulators of G protein signaling (RGS) family. We have previously applied ET to the RGS family and identified a novel, evolutionarily privileged site on the RGS domain as important for regulating RGS activity. Here we confirm through targeted mutagenesis of RGS7 that these ET-identified residues are critical for RGS domain regulation and are likely to function as global determinants of RGS function. We also discuss how the recent structure of the complex of RGS9, Gt/i1alpha-GDP-AlF4- and the effector subunit PDEgamma confirms their contact with the effector-G protein interface, forming a structural pathway that communicates from the effector-contacting surface of the G protein and RGS catalytic core domain to the catalytic interface between Galpha and RGS. These results demonstrate the effectiveness of ET for identifying binding sites and efficiently focusing mutational studies on their key residues, thereby linking raw sequence and structure data to functional information.
结构基因组学的一项关键挑战是从蛋白质结构中提取功能信息。我们展示了一个在G蛋白信号调节因子（RGS）家族背景下如何使用进化追踪（ET）方法来实现这一目标的例子。我们之前已将ET应用于RGS家族，并在RGS结构域上鉴定出一个新的、具有进化优势的位点，该位点对调节RGS活性很重要。在此，我们通过对RGS7进行定点诱变证实，这些经ET鉴定的残基对RGS结构域的调节至关重要，并且可能作为RGS功能的全局决定因素发挥作用。我们还讨论了RGS9、Gt/i1alpha-GDP-AlF4-与效应子亚基PDEgamma复合物的最新结构如何证实它们与效应子 - G蛋白界面的接触，形成一条从G蛋白的效应子接触表面和RGS催化核心结构域通向Gα与RGS之间催化界面的结构通路。这些结果证明了ET在识别结合位点以及有效地将突变研究聚焦于其关键残基方面的有效性，从而将原始的序列和结构数据与功能信息联系起来。
