1bdy | pdb_00001bdy
C2 DOMAIN FROM PROTEIN KINASE C DELTA
Structural highlights
Function[KPCD_RAT] Calcium-independent, phospholipid- and diacylglycerol (DAG)-dependent serine/threonine-protein kinase that plays contrasting roles in cell death and cell survival by functioning as a pro-apoptotic protein during DNA damage-induced apoptosis, but acting as an anti-apoptotic protein during cytokine receptor-initiated cell death, is involved in tumor suppression, is required for oxygen radical production by NADPH oxidase and acts as positive or negative regulator in platelet functional responses. Upon DNA damage, activates the promoter of the death-promoting transcription factor BCLAF1/Btf to trigger BCLAF1-mediated p53/TP53 gene transcription and apoptosis. In response to oxidative stress, interact with and activate CHUK/IKKA in the nucleus, causing the phosphorylation of p53/TP53. In the case of ER stress or DNA damage-induced apoptosis, can form a complex with the tyrosine-protein kinase ABL1 which trigger apoptosis independently of p53/TP53. In cytosol can trigger apoptosis by activating MAPK11 or MAPK14, inhibiting AKT1 and decreasing the level of X-linked inhibitor of apoptosis protein (XIAP), whereas in nucleus induces apoptosis via the activation of MAPK8 or MAPK9. Upon ionizing radiation treatment, is required for the activation of the apoptosis regulators BAX and BAK, which trigger the mitochondrial cell death pathway. Can phosphorylate MCL1 and target it for degradation which is sufficient to trigger for BAX activation and apoptosis. Is required for the control of cell cycle progression both at G1/S and G2/M phases. Mediates phorbol 12-myristate 13-acetate (PMA)-induced inhibition of cell cycle progression at G1/S phase by up-regulating the CDK inhibitor CDKN1A/p21 and inhibiting the cyclin CCNA2 promoter activity. In response to UV irradiation can phosphorylate CDK1, which is important for the G2/M DNA damage checkpoint activation. Can protect glioma cells from the apoptosis induced by TNFSF10/TRAIL, probably by inducing increased phosphorylation and subsequent activation of AKT1. Can also act as tumor suppressor upon mitogenic stimulation with PMA or TPA. In N-formyl-methionyl-leucyl-phenylalanine (fMLP)-treated cells, is required for NCF1 (p47-phox) phosphorylation and activation of NADPH oxidase activity, and regulates TNF-elicited superoxide anion production in neutrophils, by direct phosphorylation and activation of NCF1 or indirectly through MAPK1/3 (ERK1/2) signaling pathways. May also play a role in the regulation of NADPH oxidase activity in eosinophil after stimulation with IL5, leukotriene B4 or PMA. In collagen-induced platelet aggregation, acts a negative regulator of filopodia formation and actin polymerization by interacting with and negatively regulating VASP phosphorylation. Downstream of PAR1, PAR4 and CD36/GP4 receptors, regulates differentially platelet dense granule secretion; acts as a positive regulator in PAR-mediated granule secretion, whereas it negatively regulates CD36/GP4-mediated granule release. Phosphorylates MUC1 in the C-terminal and regulates the interaction between MUC1 and beta-catenin (By similarity). The catalytic subunit phosphorylates 14-3-3 proteins (YWHAB, YWHAZ and YWHAH) in a sphingosine-dependent fashion (By similarity). Truncated isoform 2 is inactive. 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 PubMedBACKGROUND: The protein kinase C (PKC) family of lipid-dependent serine/theonine kinases plays a central role in many intracellular eukaryotic signalling events. Members of the novel (delta, epsilon, eta, theta) subclass of PKC isotypes lack the Ca2+ dependence of the conventional PKC isotypes and have an N-terminal C2 domain, originally defined as V0 (variable domain zero). Biochemical data suggest that this domain serves to translocate novel PKC family members to the plasma membrane and may influence binding of PKC activators. RESULTS: The crystal structure of PKC-delta C2 domain indicates an unusual variant of the C2 fold. Structural elements unique to this C2 domain include a helix and a protruding beta hairpin which may contribute basic sequences to a membrane-interaction site. The invariant C2 motif, Pro-X-Trp, where X is any amino acid, forms a short crossover loop, departing radically from its conformation in other C2 structures, and contains a tyrosine phosphorylation site unique to PKC-delta. This loop and two others adopt quite different conformations from the equivalent Ca(2+)-binding loops of phospholipase C-delta and synaptotagmin I, and lack sequences necessary for Ca2+ coordination. CONCLUSIONS: The N-terminal sequence of Ca(2+)-independent novel PKCs defines a divergent example of a C2 structure similar to that of phospholipase C-delta. The Ca(2+)-independent regulation of novel PKCs is explained by major structural and sequence differences resulting in three non-functional Ca(2+)-binding loops. The observed structural variation and position of a tyrosine-phosphorylation site suggest the existence of distinct subclasses of C2-like domains which may have evolved distinct functional roles and mechanisms to interact with lipid membranes. Crystal structure of the C2 domain from protein kinase C-delta.,Pappa H, Murray-Rust J, Dekker LV, Parker PJ, McDonald NQ Structure. 1998 Jul 15;6(7):885-94. PMID:9687370[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences | ||||||||||||||||||
