1S9J

X-ray structure of the human mitogen-activated protein kinase kinase 1 (MEK1) in a complex with ligand and MgATP

Summary for 1S9J

• Entry DOI: 10.2210/pdb1s9j/pdb
• Related: 1S9I
• Descriptor: Dual specificity mitogen-activated protein kinase kinase 1, MAGNESIUM ION, ADENOSINE-5'-TRIPHOSPHATE, ... (5 entities in total)
• Functional Keywords: protein kinase-ligand-mgatp complex, protein-protein interactions, transferase
• Biological source: Homo sapiens (human)
• Total number of polymer chains: 1
• Total formula weight: 39023.18

Authors

Ohren, J.F.,Chen, H.,Pavlovsky, A.,Whitehead, C.,Yan, C.,McConnell, P.,Delaney, A.,Dudley, D.T.,Sebolt-Leopold, J.,Hasemann, C.A. (deposition date: 2004-02-04, release date: 2004-11-23, Last modification date: 2024-04-03)

Primary citation

Ohren, J.F.,Chen, H.,Pavlovsky, A.,Whitehead, C.,Zhang, E.,Kuffa, P.,Yan, C.,McConnell, P.,Spessard, C.,Banotai, C.,Mueller, W.T.,Delaney, A.,Omer, C.,Sebolt-Leopold, J.,Dudley, D.T.,Leung, I.K.,Flamme, C.,Warmus, J.,Kaufman, M.,Barrett, S.,Tecle, H.,Hasemann, C.A.
Structures of human MAP kinase kinase 1 (MEK1) and MEK2 describe novel noncompetitive kinase inhibition.
Nat.Struct.Mol.Biol., 11:1192-1197, 2004

PubMed Abstract: MEK1 and MEK2 are closely related, dual-specificity tyrosine/threonine protein kinases found in the Ras/Raf/MEK/ERK mitogen-activated protein kinase (MAPK) signaling pathway. Approximately 30% of all human cancers have a constitutively activated MAPK pathway, and constitutive activation of MEK1 results in cellular transformation. Here we present the X-ray structures of human MEK1 and MEK2, each determined as a ternary complex with MgATP and an inhibitor to a resolution of 2.4 A and 3.2 A, respectively. The structures reveal that MEK1 and MEK2 each have a unique inhibitor-binding pocket adjacent to the MgATP-binding site. The presence of the potent inhibitor induces several conformational changes in the unphosphorylated MEK1 and MEK2 enzymes that lock them into a closed but catalytically inactive species. Thus, the structures reported here reveal a novel, noncompetitive mechanism for protein kinase inhibition.

PubMed: 15543157
DOI: 10.1038/nsmb859

Experimental method

X-RAY DIFFRACTION (2.4 Å)