QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Wang, Q. J. Articles by Blumberg, P. M. Search for Related Content PubMed PubMed Citation Articles by Wang, Q. J. Articles by Blumberg, P. M.

Ligand Structure-Activity Requirements and Phospholipid Dependence for the Binding of Phorbol Esters to Protein Kinase D

Department of Pharmacology, University of Pittsburgh, Pittsburgh, Pennsylvania (Q.J.W.); Molecular Mechanisms of Tumor Promotion Section, Laboratory of Cellular Carcinogenesis and Tumor Promotion (Q.J.W., T.-W.F., D.Y., N.E.L., P.M.B.), and Laboratory of Medicinal Chemistry (V.E.M.), National Cancer Institute, Bethesda, Maryland; and Division of Biochemistry, Faculty of Medicine, Katholieke Universiteit Leuven, Leuven, Belgium (J.V.L.)

Although protein kinase D (PKD), like protein kinase C (PKC), possesses a C1 domain that binds phorbol esters and diacylglycerol, the structural differences from PKC within this and other domains of PKD imply differential regulation by lipids and ligands. We characterized the phorbol ester and phospholipid binding properties of a glutathione S-transferase-tagged full-length PKD and compared them with those of PKC- and -. We found that PKD is a high-affinity phorbol ester receptor for a range of structurally and functionally divergent phorbol esters and analogs and showed both similarities and differences in structure-activity relations compared with the PKCs examined. In particular, PKD had lower affinity than PKC for certain diacylglycerol analogs, which might be caused by a lysine residue at the 22 position of the PKD-C1b domain in place of the tryptophan residue at this position conserved in the PKCs. The membrane-targeting domains in PKD are largely different from those in PKC; among these differences, PKD contains a pleckstrin homology (PH) domain that is absent in PKC. However, phosphatidylinositol-4,5-bisphosphate PIP₂, a lipid ligand for some PH domains, reconstitutes phorbol 12,13-dibutyrate (PDBu) binding to PKD similarly as it does to PKC- and -, implying that the PH domain in PKD may not preferentially interact with PIP₂. Overall, the requirement of anionic phospholipids for the reconstitution of [³H]PDBu binding to PKD was intermediate between those of PKC- and -. We conclude that PKD is a high-affinity phorbol ester receptor; its lipid requirements for ligand binding are approximately comparable with those of PKC but may be differentially regulated in cells through the binding of diacylglycerol to the C1 domain.

Address correspondence to: Dr. Q. Jane Wang, Department of Pharmacology, University of Pittsburgh, E1354 Biomedical Science Tower, Pittsburgh, PA 15261. E-mail: qjw1{at}pitt.edu

This article has been cited by other articles:

				R. Jacamo, J. Sinnett-Smith, O. Rey, R. T. Waldron, and E. Rozengurt Sequential Protein Kinase C (PKC)-dependent and PKC-independent Protein Kinase D Catalytic Activation via Gq-coupled Receptors: DIFFERENTIAL REGULATION OF ACTIVATION LOOP SER744 AND SER748 PHOSPHORYLATION J. Biol. Chem., May 9, 2008; 283(19): 12877 - 12887. [Abstract] [Full Text] [PDF]

				A. Auer, J. von Blume, S. Sturany, G. von Wichert, J. Van Lint, J. Vandenheede, G. Adler, and T. Seufferlein Role of the Regulatory Domain of Protein Kinase D2 in Phorbol Ester Binding, Catalytic Activity, and Nucleocytoplasmic Shuttling Mol. Biol. Cell, September 1, 2005; 16(9): 4375 - 4385. [Abstract] [Full Text] [PDF]

				E. Rozengurt, O. Rey, and R. T. Waldron Protein Kinase D Signaling J. Biol. Chem., April 8, 2005; 280(14): 13205 - 13208. [Full Text] [PDF]

				S. Carrasco and I. Merida Diacylglycerol-dependent Binding Recruits PKC{theta} and RasGRP1 C1 Domains to Specific Subcellular Localizations in Living T Lymphocytes Mol. Biol. Cell, June 1, 2004; 15(6): 2932 - 2942. [Abstract] [Full Text] [PDF]