Evidence of ζ Protein Kinase C Involvement in Polymorphonuclear Neutrophil Integrin-dependent Adhesion and Chemotaxis

doi:10.1074/jbc.273.46.30306

Evidence of ζ Protein Kinase C Involvement in Polymorphonuclear Neutrophil Integrin-dependent Adhesion and Chemotaxis*

From the ^‡Laboratory of Immunology and Vascular Biology, Department of Pathology, and the Digestive Disease Center, Department of Medicine, Stanford University, Stanford, California 94305, the ^§Center for Molecular Biology and Medicine, the Veterans Affairs Health Care System, Palo Alto, California 94304, the ^¶Institute of General Pathology, University of Verona, 37134 Verona, Italy, and the ^**Department of Molecular Pharmacology, School of Medicine, Stanford University, Stanford, California, 94305-5332

Abstract

Classical chemoattractants and chemokines trigger integrin-dependent adhesion of blood leukocytes to vascular endothelium and also direct subsequent extravasation and migration into tissues. In studies of human polymorphonuclear neutrophil responses to formyl peptides and to interleukin 8, we show evidence of involvement of the atypical ζ protein kinase C in the signaling pathway leading to chemoattractant-triggered actin assembly, integrin-dependent adhesion, and chemotaxis. Selective inhibitors of classical and novel protein kinase C isozymes do not prevent chemoattractant-induced neutrophil adhesion and chemotaxis. In contrast, chelerythrine chloride and synthetic myristoylated peptides with sequences based on the endogenous ζ protein kinase C pseudosubstrate region block agonist-induced adhesion to fibrinogen, chemotaxis and F-actin accumulation. Biochemical analysis shows that chemoattractants trigger rapid translocation of ζ protein kinase C to the plasma membrane accompanied by rapid but transient increase of the kinase activity. Moreover, pretreatment with C3 transferase, a specific inhibitor of Rho small GTPases, blocks ζ but not α protein kinase C plasma membrane translocation. Synthetic peptides from ζ protein kinase C also inhibit phorbol ester-induced integrin-dependent adhesion but not NADPH-oxidase activation, and C3 transferase pretreatment blocks phorbol ester-triggered translocation of ζ but not α protein kinase C. These data suggest the involvement of ζ protein kinase C in chemoattractant-induced leukocyte integrin-dependent adhesion and chemotaxis. Moreover, they highlight a potential link between atypical protein kinase C isozymes and Rho signaling pathways leading to integrin-activation.

Footnotes

↵* This work was supported in part by grants from the National Institutes of Health (NIH), by an award from the Department of Veterans Affairs, and by the FACS Core Facility of the Stanford Digestive Disease Center under NIH Grant DK38707.
↵‖ Recipient of a fellowship of Dottorato di Ricerca in Biologia e Patologia Cellulare e Molecolare from the University of Verona, Verona, Italy. To whom correspondence should be addressed: Institute of General Pathology, University of Verona, Strada Le Grazie 4, 37134, Verona, Italy. Tel.: 045-8098120; Fax: 045-8098127; E-mail:clauda{at}borgoroma.univr.it.
↵2 C. Laudanna, G. Constantin, and E. C. Butcher, manuscript in preparation.
Abbreviations:

fMLP

formyl-Met-Leu-Phe

IL-8

interleukin-8

DAG

diacylglycerol

PKC

protein kinase C

PMA

phorbol myristate acetate

PBS

phosphate-buffered saline

FCS

fetal calf serum.
- Received April 27, 1998.
- Revision received August 6, 1998.
The American Society for Biochemistry and Molecular Biology, Inc.