Linn H, Ermekova K S, Rentschler S, Sparks A B, Kay B K, Sudol M
Mount Sinai School of Medicine, Department of Biochemistry, New York 10029-6574, USA.
Biol Chem. 1997 Jun;378(6):531-7. doi: 10.1515/bchm.1997.378.6.531.
The WW domain is a globular protein domain that is involved in mediating protein-protein interaction and that ultimately participates in various intracellular signaling events. The domain binds to polyproline ligands containing the xPPxY consensus (where x signifies any amino acid, P is proline and Y is tyrosine). One of the first WW domain-ligand links that was characterized in vitro was the WW domain of Yes-Associated Protein (YAP) and its WBP-1 ligand. To further characterize this molecular interaction, we used two independent approaches, both of which focused on the mutational analysis of the WBP-1 ligand. We screened repertoires of synthetic decamer peptides containing the xPPxY core of WBP-1 in which all ten positions were sequentially replaced with the remaining amino acids. In addition, we screened decamer repertoires with all permutations of the amino acids which individually increased the binding to the WW domain of YAP, as compared to the wild type. In a parallel approach, we used a phage-displayed combinatorial peptide library biased for the presence of two consecutive prolines to study ligand preferences for the WW domain of YAP. Interestingly, these two lines of investigation converged and yielded the core sequence PPPPYP, which is preferred by the YAP-WW domain. This sequence was found within the p53 (tumor suppressor) binding protein-2, a probable cognate or alternative ligand interacting with YAP.
WW 结构域是一种球状蛋白质结构域，参与介导蛋白质-蛋白质相互作用，并最终参与各种细胞内信号转导事件。该结构域与含有 xPPxY 共有序列（其中 x 表示任何氨基酸，P 是脯氨酸，Y 是酪氨酸）的多聚脯氨酸配体结合。体外鉴定的首批 WW 结构域-配体相互作用之一是 Yes 相关蛋白（YAP）的 WW 结构域及其 WBP-1 配体。为了进一步表征这种分子相互作用，我们使用了两种独立的方法，这两种方法都聚焦于 WBP-1 配体的突变分析。我们筛选了含有 WBP-1 的 xPPxY 核心的合成十肽文库，其中十个位置依次被其余氨基酸取代。此外，我们筛选了氨基酸全排列的十肽文库，与野生型相比，这些氨基酸单独增加了与 YAP 的 WW 结构域的结合。在并行方法中，我们使用了偏向于存在两个连续脯氨酸的噬菌体展示组合肽文库来研究 YAP 的 WW 结构域的配体偏好。有趣的是，这两条研究路线得出了核心序列 PPPPYP，它是 YAP-WW 结构域偏爱的序列。该序列存在于 p53（肿瘤抑制因子）结合蛋白-2 中，p53 结合蛋白-2 是一种可能与 YAP 相互作用的同源或替代配体。
