| Structural highlights
Function
PDPK1_HUMAN Serine/threonine kinase which acts as a master kinase, phosphorylating and activating a subgroup of the AGC family of protein kinases. Its targets include: protein kinase B (PKB/AKT1, PKB/AKT2, PKB/AKT3), p70 ribosomal protein S6 kinase (RPS6KB1), p90 ribosomal protein S6 kinase (RPS6KA1, RPS6KA2 and RPS6KA3), cyclic AMP-dependent protein kinase (PRKACA), protein kinase C (PRKCD and PRKCZ), serum and glucocorticoid-inducible kinase (SGK1, SGK2 and SGK3), p21-activated kinase-1 (PAK1), protein kinase PKN (PKN1 and PKN2). Plays a central role in the transduction of signals from insulin by providing the activating phosphorylation to PKB/AKT1, thus propagating the signal to downstream targets controlling cell proliferation and survival, as well as glucose and amino acid uptake and storage. Negatively regulates the TGF-beta-induced signaling by: modulating the association of SMAD3 and SMAD7 with TGF-beta receptor, phosphorylating SMAD2, SMAD3, SMAD4 and SMAD7, preventing the nuclear translocation of SMAD3 and SMAD4 and the translocation of SMAD7 from the nucleus to the cytoplasm in response to TGF-beta. Activates PPARG transcriptional activity and promotes adipocyte differentiation. Activates the NF-kappa-B pathway via phosphorylation of IKKB. The tyrosine phosphorylated form is crucial for the regulation of focal adhesions by angiotensin II. Controls proliferation, survival, and growth of developing pancreatic cells. Participates in the regulation of Ca(2+) entry and Ca(2+)-activated K(+) channels of mast cells. Essential for the motility of vascular endothelial cells (ECs) and is involved in the regulation of their chemotaxis. Plays a critical role in cardiac homeostasis by serving as a dual effector for cell survival and beta-adrenergic response. Plays an important role during thymocyte development by regulating the expression of key nutrient receptors on the surface of pre-T cells and mediating Notch-induced cell growth and proliferative responses. Provides negative feedback inhibition to toll-like receptor-mediated NF-kappa-B activation in macrophages. Isoform 3 is catalytically inactive.[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15]
Publication Abstract from PubMed
There is great interest in developing selective protein kinase inhibitors by targeting allosteric sites, but these sites often involve protein-protein or protein-peptide interfaces that are very challenging to target with small molecules. Here we present a systematic approach to targeting a functionally conserved allosteric site on the protein kinase PDK1 called the PDK1-interacting fragment (PIF)tide-binding site, or PIF pocket. More than two dozen prosurvival and progrowth kinases dock a conserved peptide tail into this binding site, which recruits them to PDK1 to become activated. Using a site-directed chemical screen, we identified and chemically optimized ligand-efficient, selective, and cell-penetrant small molecules (molecular weight approximately 380 Da) that compete with the peptide docking motif for binding to PDK1. We solved the first high-resolution structure of a peptide docking motif (PIFtide) bound to PDK1 and mapped binding energy hot spots using mutational analysis. We then solved structures of PDK1 bound to the allosteric small molecules, which revealed a binding mode that remarkably mimics three of five hot-spot residues in PIFtide. These allosteric small molecules are substrate-selective PDK1 inhibitors when used as single agents, but when combined with an ATP-competitive inhibitor, they completely suppress the activation of the downstream kinases. This work provides a promising new scaffold for the development of high-affinity PIF pocket ligands, which may be used to enhance the anticancer activity of existing PDK1 inhibitors. Moreover, our results provide further impetus for exploring the helix alphaC patches of other protein kinases as potential therapeutic targets even though they involve protein-protein interfaces.
A small-molecule mimic of a peptide docking motif inhibits the protein kinase PDK1.,Rettenmaier TJ, Sadowsky JD, Thomsen ND, Chen SC, Doak AK, Arkin MR, Wells JA Proc Natl Acad Sci U S A. 2014 Dec 30;111(52):18590-5. doi:, 10.1073/pnas.1415365112. Epub 2014 Dec 17. PMID:25518860[16]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Alessi DR, James SR, Downes CP, Holmes AB, Gaffney PR, Reese CB, Cohen P. Characterization of a 3-phosphoinositide-dependent protein kinase which phosphorylates and activates protein kinase Balpha. Curr Biol. 1997 Apr 1;7(4):261-9. PMID:9094314
- ↑ Chou MM, Hou W, Johnson J, Graham LK, Lee MH, Chen CS, Newton AC, Schaffhausen BS, Toker A. Regulation of protein kinase C zeta by PI 3-kinase and PDK-1. Curr Biol. 1998 Sep 24;8(19):1069-77. PMID:9768361
- ↑ Cheng X, Ma Y, Moore M, Hemmings BA, Taylor SS. Phosphorylation and activation of cAMP-dependent protein kinase by phosphoinositide-dependent protein kinase. Proc Natl Acad Sci U S A. 1998 Aug 18;95(17):9849-54. PMID:9707564
- ↑ Pullen N, Dennis PB, Andjelkovic M, Dufner A, Kozma SC, Hemmings BA, Thomas G. Phosphorylation and activation of p70s6k by PDK1. Science. 1998 Jan 30;279(5351):707-10. PMID:9445476
- ↑ Jensen CJ, Buch MB, Krag TO, Hemmings BA, Gammeltoft S, Frodin M. 90-kDa ribosomal S6 kinase is phosphorylated and activated by 3-phosphoinositide-dependent protein kinase-1. J Biol Chem. 1999 Sep 17;274(38):27168-76. PMID:10480933
- ↑ King CC, Gardiner EM, Zenke FT, Bohl BP, Newton AC, Hemmings BA, Bokoch GM. p21-activated kinase (PAK1) is phosphorylated and activated by 3-phosphoinositide-dependent kinase-1 (PDK1). J Biol Chem. 2000 Dec 29;275(52):41201-9. PMID:10995762 doi:10.1074/jbc.M006553200
- ↑ Scheid MP, Marignani PA, Woodgett JR. Multiple phosphoinositide 3-kinase-dependent steps in activation of protein kinase B. Mol Cell Biol. 2002 Sep;22(17):6247-60. PMID:12167717
- ↑ Taniyama Y, Weber DS, Rocic P, Hilenski L, Akers ML, Park J, Hemmings BA, Alexander RW, Griendling KK. Pyk2- and Src-dependent tyrosine phosphorylation of PDK1 regulates focal adhesions. Mol Cell Biol. 2003 Nov;23(22):8019-29. PMID:14585963
- ↑ Nilsen T, Slagsvold T, Skjerpen CS, Brech A, Stenmark H, Olsnes S. Peroxisomal targeting as a tool for assaying potein-protein interactions in the living cell: cytokine-independent survival kinase (CISK) binds PDK-1 in vivo in a phosphorylation-dependent manner. J Biol Chem. 2004 Feb 6;279(6):4794-801. Epub 2003 Nov 6. PMID:14604990 doi:10.1074/jbc.M309653200
- ↑ Balendran A, Casamayor A, Deak M, Paterson A, Gaffney P, Currie R, Downes CP, Alessi DR. PDK1 acquires PDK2 activity in the presence of a synthetic peptide derived from the carboxyl terminus of PRK2. Curr Biol. 1999 Apr 22;9(8):393-404. PMID:10226025
- ↑ Tanaka H, Fujita N, Tsuruo T. 3-Phosphoinositide-dependent protein kinase-1-mediated IkappaB kinase beta (IkkB) phosphorylation activates NF-kappaB signaling. J Biol Chem. 2005 Dec 9;280(49):40965-73. Epub 2005 Oct 5. PMID:16207722 doi:10.1074/jbc.M506235200
- ↑ Seong HA, Jung H, Choi HS, Kim KT, Ha H. Regulation of transforming growth factor-beta signaling and PDK1 kinase activity by physical interaction between PDK1 and serine-threonine kinase receptor-associated protein. J Biol Chem. 2005 Dec 30;280(52):42897-908. Epub 2005 Oct 26. PMID:16251192 doi:10.1074/jbc.M507539200
- ↑ Seong HA, Jung H, Kim KT, Ha H. 3-Phosphoinositide-dependent PDK1 negatively regulates transforming growth factor-beta-induced signaling in a kinase-dependent manner through physical interaction with Smad proteins. J Biol Chem. 2007 Apr 20;282(16):12272-89. Epub 2007 Feb 27. PMID:17327236 doi:10.1074/jbc.M609279200
- ↑ Primo L, di Blasio L, Roca C, Droetto S, Piva R, Schaffhausen B, Bussolino F. Essential role of PDK1 in regulating endothelial cell migration. J Cell Biol. 2007 Mar 26;176(7):1035-47. Epub 2007 Mar 19. PMID:17371830 doi:10.1083/jcb.200607053
- ↑ Lim WG, Chen X, Liu JP, Tan BJ, Zhou S, Smith A, Lees N, Hou L, Gu F, Yu XY, Du Y, Smith D, Verma C, Liu K, Duan W. The C-terminus of PRK2/PKNgamma is required for optimal activation by RhoA in a GTP-dependent manner. Arch Biochem Biophys. 2008 Nov 15;479(2):170-8. doi: 10.1016/j.abb.2008.09.008., Epub 2008 Sep 22. PMID:18835241 doi:10.1016/j.abb.2008.09.008
- ↑ Rettenmaier TJ, Sadowsky JD, Thomsen ND, Chen SC, Doak AK, Arkin MR, Wells JA. A small-molecule mimic of a peptide docking motif inhibits the protein kinase PDK1. Proc Natl Acad Sci U S A. 2014 Dec 30;111(52):18590-5. doi:, 10.1073/pnas.1415365112. Epub 2014 Dec 17. PMID:25518860 doi:http://dx.doi.org/10.1073/pnas.1415365112
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