3Q4Z

Structure of unphosphorylated PAK1 kinase domain

Summary for 3Q4Z

• Entry DOI: 10.2210/pdb3q4z/pdb
• Related: 3Q52 3Q53
• Descriptor: Serine/threonine-protein kinase PAK 1, MAGNESIUM ION, PHOSPHOAMINOPHOSPHONIC ACID-ADENYLATE ESTER, ... (4 entities in total)
• Functional Keywords: kinase domain, signalling pathway, transferase
• Biological source: Homo sapiens (human)
• Cellular location: Cytoplasm: Q13153
• Total number of polymer chains: 2
• Total formula weight: 69559.88

Authors

Wang, J.,Wu, J.-W.,Wang, Z.-X. (deposition date: 2010-12-26, release date: 2011-12-21, Last modification date: 2023-11-01)

Primary citation

Wang, J.,Wu, J.-W.,Wang, Z.-X.
Structural insights into the autoactivation mechanism of p21-activated protein kinase
Structure, 19:1752-1761, 2011

PubMed Abstract: p21-activated kinases (PAKs) play an important role in diverse cellular processes. Full activation of PAKs requires autophosphorylation of a critical threonine/serine located in the activation loop of the kinase domain. Here we report crystal structures of the phosphorylated and unphosphorylated PAK1 kinase domain. The phosphorylated PAK1 kinase domain has a conformation typical of all active protein kinases. Interestingly, the structure of the unphosphorylated PAK1 kinase domain reveals an unusual dimeric arrangement expected in an authentic enzyme-substrate complex, in which the activation loop of the putative "substrate" is projected into the active site of the "enzyme." The enzyme is bound to AMP-PNP and has an active conformation, whereas the substrate is empty and adopts an inactive conformation. Thus, the structure of the asymmetric homodimer mimics a trans-autophosphorylation complex, and suggests that unphosphorylated PAK1 could dynamically adopt both the active and inactive conformations in solution.

PubMed: 22153498
DOI: 10.1016/j.str.2011.10.013

Experimental method

X-RAY DIFFRACTION (1.887 Å)