Activation of the extracellular signal-regulated kinase-2 (ERK2) by phosphorylation has been shown to involve changes in protein dynamics, as determined by hydrogen-deuterium exchange mass spectrometry (HDX-MS) and NMR relaxation dispersion measurements. These can be described by a global exchange between two conformational states of the active kinase, named ‘L’ and ‘R,’ where R is associated with a catalytically productive ATP-binding mode. An ATP-competitive ERK1/2 inhibitor, Vertex-11e, has properties of conformation selection for the R-state, revealing movements of the activation loop that are allosterically coupled to the kinase active site. However, the features of inhibitors important for R-state selection are unknown. Here, we survey a panel of ATP-competitive ERK inhibitors using HDX-MS and NMR and identify 14 new molecules with properties of R-state selection. They reveal effects propagated to distal regions in the P+1 and helix αF segments surrounding the activation loop, as well as helix αL16. Crystal structures of inhibitor complexes with ERK2 reveal systematic shifts in the Gly loop and helix αC, mediated by a Tyr-Tyr ring stacking interaction and the conserved Lys-Glu salt bridge. The findings suggest a model for the R-state involving small movements in the N-lobe that promote compactness within the kinase active site and alter mobility surrounding the activation loop. Such properties of conformation selection might be exploited to modulate the protein docking interface used by ERK substrates and effectors.

中文翻译：

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ATP 竞争性抑制剂的构象选择和 ERK2 中的变构通讯

通过氢-氘交换质谱 (HDX-MS) 和 NMR 弛豫色散测量确定，磷酸化对细胞外信号调节激酶 2 (ERK2) 的激活涉及蛋白质动力学的变化。这些可以通过活性激酶的两种构象状态（称为“L”和“R”）之间的全局交换来描述，其中 R 与催化生产的 ATP 结合模式相关。 ATP 竞争性 ERK1/2 抑制剂 Vertex-11e 具有 R 状态构象选择特性，揭示了与激酶活性位点变构耦合的激活环的运动。然而，对于 R 态选择重要的抑制剂的特征尚不清楚。在这里，我们使用 HDX-MS 和 NMR 调查了一组 ATP 竞争性 ERK 抑制剂，并鉴定了 14 种具有 R 态选择特性的新分子。他们揭示了传播到激活环周围的P +1 和螺旋 αF 片段以及螺旋 αL16 远端区域的效应。抑制剂与 ERK2 复合物的晶体结构揭示了 Gly 环和螺旋 αC 的系统变化，这是由 Tyr-Tyr 环堆积相互作用和保守的 Lys-Glu 盐桥介导的。研究结果提出了一个 R 状态模型，涉及 N 叶中的小运动，从而促进激酶活性位点内的致密性并改变激活环周围的活动性。构象选择的这种特性可用于调节 ERK 底物和效应器使用的蛋白质对接界面。