Architecture of the MKK6-p38α complex defines the basis of MAPK specificity and activation

• 成果类型: Article
• 署名作者: Juyoux, Pauline; Galdadas, Ioannis; Gobbo, Dorothea; von Velsen, Jill; Pelosse, Martin; Tully, Mark; Vadas, Oscar; Gervasio, Francesco Luigi; Pellegrini, Erika; Bowler, Matthew W.
• 署名单位: European Molecular Biology Laboratory (EMBL); University of Geneva; University of Geneva; European Synchrotron Radiation Facility (ESRF); University of Geneva; University of London; University College London; University of London; Birkbeck University London; University College London; Swiss Institute of Bioinformatics
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-9027
• DOI: 10.1126/science.add7859
• 发表日期: 2023-09-15
• 页码: 1217-1224
• 关键词: cryo-em structure; crystal-structure; protein; phosphorylation; binding; reveals; kinases; simulations; infection; p38-alpha

摘要

The mitogen-activated protein kinase (MAPK) p38 alpha is a central component of signaling in inflammation and the immune response and is, therefore, an important drug target. Little is known about the molecular mechanism of its activation by double phosphorylation from MAPK kinases (MAP2Ks), because of the challenge of trapping a transient and dynamic heterokinase complex. We applied a multidisciplinary approach to generate a structural model of p38 alpha in complex with its MAP2K, MKK6, and to understand the activation mechanism. Integrating cryo-electron microscopy with molecular dynamics simulations, hydrogen-deuterium exchange mass spectrometry, and experiments in cells, we demonstrate a dynamic, multistep phosphorylation mechanism, identify catalytically relevant interactions, and show that MAP2K-disordered amino termini determine pathway specificity. Our work captures a fundamental step of cell signaling: a kinase phosphorylating its downstream target kinase.