STRUCTURE OF HUMAN PDK1 KINASE DOMAIN IN COMPLEX WITH LY333531
[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.              
Publication Abstract from PubMed
LY333531, BIM-1, BIM-2, BIM-3, and BIM-8 are bisindolyl maleimide-based, nanomolar protein kinase C inhibitors. LY333531, a PKCbeta-specific inhibitor, is in clinical trials against diabetes and cardiac ventricular hypertrophy complications. Specificity analysis with a panel of 29 protein kinases reveals that these bisindolyl maleimide inhibitors also inhibit PDK1, a key kinase from the insulin signaling pathway, albeit in the lower microM range. To understand the molecular basis of inhibition, the PDK1 kinase domain was cocrystallized with these bisindolyl maleimide inhibitors. The inhibitor complexes represent the first structural description of this class of compounds, revealing their unusual nonplanar conformation within the ATP binding site and also explaining the higher inhibitory potential of LY33331 compared to the BIM compounds toward PDK1. A combination of site-directed mutagenesis and essential dynamics analysis gives further insight into PDK1 and also PKC inhibition by these compounds, and may aid inhibitor design.
Interactions of LY333531 and other bisindolyl maleimide inhibitors with PDK1.,Komander D, Kular GS, Schuttelkopf AW, Deak M, Prakash KR, Bain J, Elliott M, Garrido-Franco M, Kozikowski AP, Alessi DR, van Aalten DM Structure. 2004 Feb;12(2):215-26. PMID:14962382
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.