1zrz
From Proteopedia
Crystal Structure of the Catalytic Domain of Atypical Protein Kinase C-iota
Structural highlights
FunctionKPCI_HUMAN Calcium- and diacylglycerol-independent serine/ threonine-protein kinase that plays a general protective role against apoptotic stimuli, is involved in NF-kappa-B activation, cell survival, differentiation and polarity, and contributes to the regulation of microtubule dynamics in the early secretory pathway. Is necessary for BCR-ABL oncogene-mediated resistance to apoptotic drug in leukemia cells, protecting leukemia cells against drug-induced apoptosis. In cultured neurons, prevents amyloid beta protein-induced apoptosis by interrupting cell death process at a very early step. In glioblastoma cells, may function downstream of phosphatidylinositol 3-kinase (PI(3)K) and PDPK1 in the promotion of cell survival by phosphorylating and inhibiting the pro-apoptotic factor BAD. Can form a protein complex in non-small cell lung cancer (NSCLC) cells with PARD6A and ECT2 and regulate ECT2 oncogenic activity by phosphorylation, which in turn promotes transformed growth and invasion. In response to nerve growth factor (NGF), acts downstream of SRC to phosphorylate and activate IRAK1, allowing the subsequent activation of NF-kappa-B and neuronal cell survival. Functions in the organization of the apical domain in epithelial cells by phosphorylating EZR. This step is crucial for activation and normal distribution of EZR at the early stages of intestinal epithelial cell differentiation. Forms a protein complex with LLGL1 and PARD6B independently of PARD3 to regulate epithelial cell polarity. Plays a role in microtubule dynamics in the early secretory pathway through interaction with RAB2A and GAPDH and recruitment to vesicular tubular clusters (VTCs). In human coronary artery endothelial cells (HCAEC), is activated by saturated fatty acids and mediates lipid-induced apoptosis.[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedAtypical protein kinases C (aPKCs) play critical roles in signaling pathways that control cell growth, differentiation and survival. Therefore, they constitute attractive targets for the development of novel therapeutics against cancer. The crystal structure of the catalytic domain of atypical PKCiota in complex with the bis(indolyl)maleimide inhibitor BIM1 has been determined at 3.0A resolution within the frame of the European Structural Proteomics Project SPINE. The overall structure exhibits the classical bilobal kinase fold and is in its fully activated form. Both phosphorylation sites (Thr403 in the activation loop, and Thr555 in the turn motif) are well defined in the structure and form intramolecular ionic contacts that make an important contribution in stabilizing the active conformation of the catalytic subunit. The phosphorylation site in the hydrophobic motif of atypical PKCs is replaced by the phosphorylation mimic glutamate and this is also clearly seen in the structure of PKCiota (residue 574). This structure determination for the first time provides the architecture of the turn motif phosphorylation site, which is characteristic for PKCs and PKB/AKT, and is completely different from that in PKA. The bound BIM1 inhibitor blocks the ATP-binding site and puts the kinase domain into an intermediate open conformation. The PKCiota-BIM1 complex is the first kinase domain crystal structure of any atypical PKC and constitutes the basis for rational drug design for selective PKCiota inhibitors. Crystal structure of the catalytic domain of human atypical protein kinase C-iota reveals interaction mode of phosphorylation site in turn motif.,Messerschmidt A, Macieira S, Velarde M, Badeker M, Benda C, Jestel A, Brandstetter H, Neuefeind T, Blaesse M J Mol Biol. 2005 Sep 30;352(4):918-31. PMID:16125198[15] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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