Btk SH2-kinase interface is critical for allosteric kinase activation and its targeting inhibits B-cell neoplasms
Btk SH2-kinase interface is critical for allosteric kinase activation and its targeting inhibits B-cell neoplasms
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DOI：
10.1038/s41467-020-16128-5
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发表时间：
2020-05-08
影响因子：
16.6
通讯作者：
Hantschel, Oliver
中科院分区：
文献类型：
--
作者：
Duarte, Daniel P.;Lamontanara, Allan J.;Hantschel, Oliver
布鲁顿酪氨酸激酶（Btk）对b细胞的成熟和激活至关重要。Btk功能丧失突变导致人类x连锁无球蛋白血症（XLA）。相反，Btk信号可以维持几种可以用酪氨酸激酶抑制剂（TKIs）治疗的b细胞肿瘤的生长。在这里，我们揭示了SH2结构域中某些XLA突变强烈干扰Btk激活的结构机制。使用分子动力学（MD）模拟和小角度x射线散射（SAXS）的组合，我们发现了Btk激活所需的SH2和激酶结构域之间的变弹性界面，并且多个XLA突变映射到该界面。由于变构相互作用提供了独特的靶向机会，我们开发了一种与SH2结构域结合的工程重复体蛋白，能够破坏SH2激酶的相互作用。该重复体阻止野生型和tki抗性Btk的激活，抑制Btk依赖的信号传导和恶性b细胞的增殖。因此，sh2 -激酶界面对于Btk的激活和变构抑制的靶点是至关重要的。组成型Btk信号驱动几种b细胞癌。在这里，作者展示了Btk的SH2结构域和激酶结构域之间的关键变构分子内相互作用，并提出了一种抑制野生型和酪氨酸激酶抑制剂抗性Btk的替代方法。
Bruton's tyrosine kinase (Btk) is critical for B-cell maturation and activation. Btk loss-of-function mutations cause human X-linked agammaglobulinemia (XLA). In contrast, Btk signaling sustains growth of several B-cell neoplasms which may be treated with tyrosine kinase inhibitors (TKIs). Here, we uncovered the structural mechanism by which certain XLA mutations in the SH2 domain strongly perturb Btk activation. Using a combination of molecular dynamics (MD) simulations and small-angle X-ray scattering (SAXS), we discovered an allosteric interface between the SH2 and kinase domain required for Btk activation and to which multiple XLA mutations map. As allosteric interactions provide unique targeting opportunities, we developed an engineered repebody protein binding to the SH2 domain and able to disrupt the SH2-kinase interaction. The repebody prevents activation of wild-type and TKI-resistant Btk, inhibiting Btk-dependent signaling and proliferation of malignant B-cells. Therefore, the SH2-kinase interface is critical for Btk activation and a targetable site for allosteric inhibition. Constitutive Btk signaling drives several B-cell cancers. Here the authors demonstrate key allosteric intramolecular interactions between the SH2 domain and the kinase domain of Btk, and propose an alternative approach for inhibition of both wild-type and tyrosine kinase inhibitor-resistant Btk.