Discovery of a novel allosteric inhibitor-binding site in ERK5: comparison with the canonical kinase hinge ATP-binding site.
Discovery of a novel allosteric inhibitor-binding site in ERK5: comparison with the canonical kinase hinge ATP-binding site.
复制标题
DOI：
10.1107/s2059798316004502
复制
发表时间：
2016-05
期刊：
影响因子：
--
通讯作者：
Ogg D
中科院分区：
文献类型：
--
作者：
Chen H;Tucker J;Wang X;Gavine PR;Phillips C;Augustin MA;Schreiner P;Steinbacher S;Preston M;Ogg D
MAP激酶ERK5与XMD8-92和四种新的抑制剂形成的复合体的晶体结构表明，在αC螺旋与蛋白激酶P-环之间存在变构结合部位。在这个位点上的结合将P-环移到ATP结合部位，并被证明是ATP竞争的。MAP激酶是多种生化信号的结合点，参与多种细胞过程，如增殖、分化、转录调控和发育等。ERK5(MAPK7)是MAP激酶家族的一员，参与多种细胞表面受体的下游信号通路，包括受体酪氨酸激酶和G蛋白偶联受体。在目前的研究中，报道了与ERK5抑制剂共结晶的五种结构的ERK5激酶结构域。有趣的是，其中三个化合物结合在ERK5上一个新的变构结合部位，而另外两个结合在典型的ATP结合部位。抑制剂在变构部位的结合伴随着P-环移位到ATP结合部位，并且在ERK5激酶活性的酶分析中被证明是ATP竞争的。激酶选择性数据显示，与结合在典型的ATP结合位点上的两种抑制剂相比，最有效的变构抑制剂表现出更好的激酶选择性。对这些结构进行了分析，并与以前发表的ERK5-抑制剂复合体结构(PDB条目4b99)以及与变构抑制剂复合体中的其他三种激酶(CDK2、ITK和MEK)的结构进行了比较。
Crystal structures of the MAP kinase ERK5 in complex with XMD8-92 and four novel inhibitors reveal an allosteric binding site between the kinase P-loop and αC helix. Binding at this site displaces the P-loop into the ATP-binding site and was shown to be ATP-competitive. MAP kinases act as an integration point for multiple biochemical signals and are involved in a wide variety of cellular processes such as proliferation, differentiation, regulation of transcription and development. As a member of the MAP kinase family, ERK5 (MAPK7) is involved in the downstream signalling pathways of various cell-surface receptors, including receptor tyrosine kinases and G protein-coupled receptors. In the current study, five structures of the ERK5 kinase domain co-crystallized with ERK5 inhibitors are reported. Interestingly, three of the compounds bind at a novel allosteric binding site in ERK5, while the other two bind at the typical ATP-binding site. Binding of inhibitors at the allosteric site is accompanied by displacement of the P-loop into the ATP-binding site and is shown to be ATP-competitive in an enzymatic assay of ERK5 kinase activity. Kinase selectivity data show that the most potent allosteric inhibitor exhibits superior kinase selectivity compared with the two inhibitors that bind at the canonical ATP-binding site. An analysis of these structures and comparison with both a previously published ERK5–inhibitor complex structure (PDB entry 4b99) and the structures of three other kinases (CDK2, ITK and MEK) in complex with allosteric inhibitors are presented.