Institute of Physical and Theoretical Chemistry, Goethe-University Frankfurt, Max-von-Laue-Str. 7, Frankfurt am Main, Germany.
Frankfurt Institute for Advanced Studies, Ruth-Moufang-Str. 1, Frankfurt am Main, Germany.
Nat Commun. 2024 Nov 2;15(1):9486. doi: 10.1038/s41467-024-53772-7.
Embedding of cell-surface receptors into a membrane defines their dynamics but also complicates experimental characterization of their signaling complexes. The hepatocyte growth factor receptor MET is a receptor tyrosine kinase involved in cellular processes such as proliferation, migration, and survival. It is also targeted by the pathogen Listeria monocytogenes, whose invasion protein, internalin B (InlB), binds to MET, forming a signaling dimer that triggers pathogen internalization. Here we use an integrative structural biology approach, combining molecular dynamics simulations and single-molecule Förster resonance energy transfer (smFRET) in cells, to investigate the early stages of MET activation. Our simulations show that InlB binding stabilizes MET in a conformation that promotes dimer formation. smFRET reveals that the in situ dimer structure closely resembles one of two previously published crystal structures, though with key differences. This study refines our understanding of MET activation and provides a methodological framework for studying other plasma membrane receptors.
细胞膜受体的嵌入不仅定义了它们的动力学特性，还使得对其信号复合物进行实验表征变得复杂。肝细胞生长因子受体 MET 是一种受体酪氨酸激酶，参与细胞增殖、迁移和存活等过程。它也是病原体李斯特菌的作用靶点，其入侵蛋白内林素 B（InlB）与 MET 结合，形成一个信号二聚体，触发病原体内化。在这里，我们使用整合结构生物学方法，结合分子动力学模拟和细胞内的单分子Förster 共振能量转移（smFRET），研究 MET 激活的早期阶段。我们的模拟表明，InlB 结合将 MET 稳定在一种促进二聚体形成的构象中。smFRET 揭示了原位二聚体结构与之前发表的两种晶体结构之一非常相似，但存在关键差异。这项研究深化了我们对 MET 激活的理解，并为研究其他质膜受体提供了方法学框架。
