Structure of the complex between calmodulin and a functional construct of eukaryotic elongation factor 2 kinase bound to an ATP-competitive inhibitor.
Structure of the complex between calmodulin and a functional construct of eukaryotic elongation factor 2 kinase bound to an ATP-competitive inhibitor.
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DOI：
10.1016/j.jbc.2023.104813
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发表时间：
2023-06
影响因子：
4.8
通讯作者：
Ghose, Ranajeet
中科院分区：
文献类型：
--
作者：
Piserchio, Andrea;Isiorho, Eta A;Dalby, Kevin N;Ghose, Ranajeet
钙调素激活的α-激酶，真核细胞延伸因子2激酶（eEF-2K），通过特异性磷酸化和降低鸟苷三磷酸酶，真核细胞延伸因子2（eEF-2）的核糖体亲和力，作为翻译延伸的主要调节因子。鉴于其在基本细胞过程中的关键作用，eEF-2K的失调与多种人类疾病有关，包括心血管系统疾病、慢性神经病和许多癌症，使其成为关键的药理学靶标。在缺乏高分辨率结构信息的情况下，高通量筛选工作已经产生了有望作为eEF-2K拮抗剂的小分子候选物。其中主要的是ATP竞争性吡啶并嘧啶二酮抑制剂A-484954，相对于一组“典型”蛋白激酶，其对eEF-2K显示出高特异性。A-484954已被证明在几种疾病状态的动物模型中具有一定程度的疗效。它还被广泛用作eEF-2K特异性生物化学和细胞生物学研究中的试剂。然而，由于缺乏结构信息，A-484954介导的eEF-2K抑制的确切机制仍不清楚。利用我们对eEF-2K的钙调素可激活催化核心的鉴定，以及我们最近对其长期难以捉摸的结构的测定，我们在这里提出了A-484954对其特异性抑制的结构基础。该结构代表了α-激酶家族成员的第一个与受体结合的催化结构域，使A-484954变体的现有结构-活性关系数据合理化，并为进一步优化该支架以增强对eEF-2K的特异性/效力奠定了基础。
The calmodulin-activated α-kinase, eukaryotic elongation factor 2 kinase (eEF-2K), serves as a master regulator of translational elongation by specifically phosphorylating and reducing the ribosome affinity of the guanosine triphosphatase, eukaryotic elongation factor 2 (eEF-2). Given its critical role in a fundamental cellular process, dysregulation of eEF-2K has been implicated in several human diseases, including those of the cardiovascular system, chronic neuropathies, and many cancers, making it a critical pharmacological target. In the absence of high-resolution structural information, high-throughput screening efforts have yielded small-molecule candidates that show promise as eEF-2K antagonists. Principal among these is the ATP-competitive pyrido-pyrimidinedione inhibitor, A-484954, which shows high specificity toward eEF-2K relative to a panel of “typical” protein kinases. A-484954 has been shown to have some degree of efficacy in animal models of several disease states. It has also been widely deployed as a reagent in eEF-2K-specific biochemical and cell-biological studies. However, given the absence of structural information, the precise mechanism of the A-484954-mediated inhibition of eEF-2K has remained obscure. Leveraging our identification of the calmodulin-activatable catalytic core of eEF-2K, and our recent determination of its long-elusive structure, here we present the structural basis for its specific inhibition by A-484954. This structure, which represents the first for an inhibitor-bound catalytic domain of a member of the α-kinase family, enables rationalization of the existing structure–activity relationship data for A-484954 variants and lays the groundwork for further optimization of this scaffold to attain enhanced specificity/potency against eEF-2K.