2BIY

Structure of PDK1-S241A mutant kinase domain

Summary for 2BIY

• Entry DOI: 10.2210/pdb2biy/pdb
• Related: 1H1W 1OKY 1OKZ 1UU3 1UU7 1UU8 1UU9 1UVR 1W1D 1W1G 1W1H
• Descriptor: 3-PHOSPHOINOSITIDE DEPENDENT PROTEIN KINASE-1, GLYCEROL, SULFATE ION, ... (5 entities in total)
• Functional Keywords: agc kinase, ac-helix, atp-binding, phosphorylation, phosphoinositide dependent protein kinase, pi3-kinase signalling, pif-pocket, pka, pkb, t-loop mutant, serine-threonine-protein kinase, transferase
• Biological source: HOMO SAPIENS (HUMAN)
• Total number of polymer chains: 1
• Total formula weight: 37226.99

Authors

Komander, D.,Kular, G.S.,Deak, M.,Alessi, D.R.,van Aalten, D.M.F. (deposition date: 2005-01-26, release date: 2005-02-23, Last modification date: 2023-12-13)

Primary citation

Komander, D.,Kular, G.,Deak, M.,Alessi, D.R.,van Aalten, D.M.
Role of T-loop phosphorylation in PDK1 activation, stability, and substrate binding.
J. Biol. Chem., 280:18797-18802, 2005

PubMed Abstract: 3-Phosphoinositide-dependent protein kinase-1 (PDK1) phosphorylates the T-loop of several AGC (cAMP-dependent, cGMP-dependent, protein kinase C) family protein kinases, resulting in their activation. Previous structural studies have revealed that the alpha C-helix, located in the small lobe of the kinase domain of PDK1, is a key regulatory element, as it links a substrate interacting site termed the hydrophobic motif (HM) pocket with the phosphorylated Ser-241 in the T-loop. In this study we have demonstrated by mutational analysis that interactions between the phosphorylated Ser-241 and the alpha C-helix are not required for PDK1 activity or substrate binding through the HM-pocket but are necessary for PDK1 to be activated or stabilized by a peptide that binds to this site. The structure of an inactive T-loop mutant of PDK1, in which Ser-241 is changed to Ala, was also determined. This structure, together with surface plasmon resonance binding studies, demonstrates that the PDK1(S241A)-inactive mutant possesses an intact HM-pocket as well as an ordered alpha C-helix. These findings reveal that the integrity of the alpha C-helix and HM-pocket in PDK1 is not regulated by T-loop phosphorylation.

PubMed: 15741170
DOI: 10.1074/jbc.M500977200

Experimental method

X-RAY DIFFRACTION (1.95 Å)