Protein kinase C-delta associates with vimentin intermediate filaments in differentiated HL60 cells.
The subcellular localization of protein kinase C (PKC)-delta was determined in HL60 cells differentiated toward monocytes/macrophages by treatment with TPA. PKC-delta was detected in the nucleus and cytoplasm of differentiated HL60 cells and, more specifically, associated with structures resembling intermediate filaments. Indirect immunostaining revealed that PKC-delta colocalized with vimentin in the cytosol and perinuclear region of these cells. Immunoprecipitation studies showed that PKC-delta was in an active (autophosphorylated) state in differentiated HL60 cells and that vimentin immunoprecipitated from these cells was also phosphorylated. Treatment of HL60 cells with the PKC-specific inhibitor chelerythrine decreased the phosphorylation of vimentin. These data suggest that vimentin is a substrate for PKC-delta and that this PKC isoenzyme may play a specific role in the regulation of shape change and cell adhesion during HL60 differentiation.
Owen
P J
PJ
Department of Immunology, Birmingham University Medical School, United Kingdom.
Johnson
G D
GD
Lord
J M
JM
D000918:Antibody Specificity; D002454:Cell Differentiation / Q000502:physiology; D002467:Cell Nucleus / Q000737:chemistry; D003703:Demecolcine; D018922:HL-60 Cells / Q000166:cytology / Q000201:enzymology*; D006801:Humans; D007150:Immunohistochemistry; D007382:Intermediate Filaments / Q000378:metabolism; D007527:Isoenzymes / Q000032:analysis / Q000276:immunology / Q000378:metabolism*; D009000:Monocytes / Q000166:cytology / Q000201:enzymology; D010766:Phosphorylation; D011493:Protein Kinase C / Q000032:analysis / Q000276:immunology / Q000378:metabolism*; D051745:Protein Kinase C-delta; D013347:Subcellular Fractions / Q000737:chemistry; D014746:Vimentin / Q000032:analysis / Q000378:metabolism*
D007527:Isoenzymes; D014746:Vimentin; C497258:PRKCD protein, human; D011493:Protein Kinase C; D051745:Protein Kinase C-delta; D003703:Demecolcine