2wh0
From Proteopedia
Recognition of an intrachain tandem 14-3-3 binding site within protein kinase C epsilon
Structural highlights
Function[1433Z_HUMAN] Adapter protein implicated in the regulation of a large spectrum of both general and specialized signaling pathways. Binds to a large number of partners, usually by recognition of a phosphoserine or phosphothreonine motif. Binding generally results in the modulation of the activity of the binding partner.[1] [2] [3] [4] [5] [KPCE_HUMAN] Calcium-independent, phospholipid- and diacylglycerol (DAG)-dependent serine/threonine-protein kinase that plays essential roles in the regulation of multiple cellular processes linked to cytoskeletal proteins, such as cell adhesion, motility, migration and cell cycle, functions in neuron growth and ion channel regulation, and is involved in immune response, cancer cell invasion and regulation of apoptosis. Mediates cell adhesion to the extracellular matrix via integrin-dependent signaling, by mediating angiotensin-2-induced activation of integrin beta-1 (ITGB1) in cardiac fibroblasts. Phosphorylates MARCKS, which phosphorylates and activates PTK2/FAK, leading to the spread of cardiomyocytes. Involved in the control of the directional transport of ITGB1 in mesenchymal cells by phosphorylating vimentin (VIM), an intermediate filament (IF) protein. In epithelial cells, associates with and phosphorylates keratin-8 (KRT8), which induces targeting of desmoplakin at desmosomes and regulates cell-cell contact. Phosphorylates IQGAP1, which binds to CDC42, mediating epithelial cell-cell detachment prior to migration. In HeLa cells, contributes to hepatocyte growth factor (HGF)-induced cell migration, and in human corneal epithelial cells, plays a critical role in wound healing after activation by HGF. During cytokinesis, forms a complex with YWHAB, which is crucial for daughter cell separation, and facilitates abscission by a mechanism which may implicate the regulation of RHOA. In cardiac myocytes, regulates myofilament function and excitation coupling at the Z-lines, where it is indirectly associated with F-actin via interaction with COPB1. During endothelin-induced cardiomyocyte hypertrophy, mediates activation of PTK2/FAK, which is critical for cardiomyocyte survival and regulation of sarcomere length. Plays a role in the pathogenesis of dilated cardiomyopathy via persistent phosphorylation of troponin I (TNNI3). Involved in nerve growth factor (NFG)-induced neurite outgrowth and neuron morphological change independently of its kinase activity, by inhibition of RHOA pathway, activation of CDC42 and cytoskeletal rearrangement. May be involved in presynaptic facilitation by mediating phorbol ester-induced synaptic potentiation. Phosphorylates gamma-aminobutyric acid receptor subunit gamma-2 (GABRG2), which reduces the response of GABA receptors to ethanol and benzodiazepines and may mediate acute tolerance to the intoxicating effects of ethanol. Upon PMA treatment, phosphorylates the capsaicin- and heat-activated cation channel TRPV1, which is required for bradykinin-induced sensitization of the heat response in nociceptive neurons. Is able to form a complex with PDLIM5 and N-type calcium channel, and may enhance channel activities and potentiates fast synaptic transmission by phosphorylating the pore-forming alpha subunit CACNA1B (CaV2.2). In prostate cancer cells, interacts with and phosphorylates STAT3, which increases DNA-binding and transcriptional activity of STAT3 and seems to be essential for prostate cancer cell invasion. Downstream of TLR4, plays an important role in the lipopolysaccharide (LPS)-induced immune response by phosphorylating and activating TICAM2/TRAM, which in turn activates the transcription factor IRF3 and subsequent cytokines production. In differentiating erythroid progenitors, is regulated by EPO and controls the protection against the TNFSF10/TRAIL-mediated apoptosis, via BCL2. May be involved in the regulation of the insulin-induced phosphorylation and activation of AKT1.[6] [7] [8] [9] [10] [11] [12] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe phosphoserine/threonine binding protein 14-3-3 stimulates the catalytic activity of protein kinase C-epsilon (PKCepsilon) by engaging two tandem phosphoserine-containing motifs located between the PKCepsilon regulatory and catalytic domains (V3 region). Interaction between 14-3-3 and this region of PKCepsilon is essential for the completion of cytokinesis. Here, we report the crystal structure of 14-3-3zeta bound to a synthetic diphosphorylated PKCepsilon V3 region revealing how a consensus 14-3-3 site and a divergent 14-3-3 site cooperate to bind to 14-3-3 and so activate PKCepsilon. Thermodynamic data show a markedly enhanced binding affinity for two-site phosphopeptides over single-site 14-3-3 binding motifs and identifies Ser 368 as a gatekeeper phosphorylation site in this physiologically relevant 14-3-3 ligand. This dual-site intra-chain recognition has implications for other 14-3-3 targets, which seem to have only a single 14-3-3 motif, as other lower affinity and cryptic 14-3-3 gatekeeper sites might exist. Recognition of an intra-chain tandem 14-3-3 binding site within PKCepsilon.,Kostelecky B, Saurin AT, Purkiss A, Parker PJ, McDonald NQ EMBO Rep. 2009 Sep;10(9):983-9. Epub 2009 Aug 7. PMID:19662078[13] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| |||||||||||||||||||||||
