Regulation of (1-3)-beta-glucan-stimulated Ca(2+) influx by protein kinase C in NR8383 alveolar macrophages.
Stimulation of (1-3)-beta-glucan receptors results in Ca(2+) influx through receptor-operated channels in alveolar macrophages (AMs), but the mechanism(s) regulating Ca(2+) influx is still undefined. In this study we investigated the role of protein kinase C (PKC) regulation of Ca(2+) influx in the NR8383 AM cell line using the particulate (1-3)-beta-glucan receptor agonist zymosan. PKC inhibition with calphostin C (CC) or bisindolymaleimide I (BSM) significantly reduced zymosan-induced Ca(2+) influx, whereas activation of PKC with phorbol-12-myristate 13-acetate (PMA) or 1, 2-dioctanoyl-sn-glycerol (DOG) mimicked zymosan, inducing a concentration-dependent Ca(2+) influx. This influx was dependent on extracellular Ca(2+) and inhibited by the receptor-operated Ca(2+) channel blocker SK&F96365, indicating that zymosan and PKC activate Ca(2+) influx through a similar pathway. NR8383 AMs expressed one new PKC isoform (delta) and two atypical PKC isoforms (iota and lambda), but conventional PKC isoforms were not present. Stimulation with zymosan resulted in a translocation of PKC-delta from the cytosol to the membrane fraction. Furthermore, inhibition of protein tyrosine kinases (PTKs) with genistein prevented zymosan-stimulated Ca(2+) influx and PKC-delta translocation. These results suggest that PKC-delta plays a critical role in regulating (1-3)-beta-glucan receptor activated Ca(2+) influx in NR8383 AMs and PKC-delta translocation is possibly dependent on PTK activity.
Mörk
A C
AC
Department of Pediatrics, University of Texas Health Science Center, San Antonio, Texas 78284, USA.
Sun
X
X
Liu
X
X
Rodriguez
D
D
Martinez
J R
JR
Castro
R
R
Zhang
G H
GH
D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002118:Calcium / Q000378:metabolism*; D002460:Cell Line; D004791:Enzyme Inhibitors / Q000494:pharmacology; D019833:Genistein / Q000494:pharmacology; D007211:Indoles / Q000494:pharmacology; D007527:Isoenzymes / Q000378:metabolism; D007700:Kinetics; D016676:Macrophages, Alveolar / Q000187:drug effects / Q000378:metabolism*; D008301:Maleimides / Q000494:pharmacology; D009281:Naphthalenes / Q000494:pharmacology; D011493:Protein Kinase C / Q000378:metabolism*; D051745:Protein Kinase C-delta; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D051381:Rats; D011971:Receptors, Immunologic / Q000187:drug effects / Q000502:physiology*; D015054:Zymosan / Q000494:pharmacology*
D004791:Enzyme Inhibitors; D007211:Indoles; D007527:Isoenzymes; D008301:Maleimides; D009281:Naphthalenes; D011971:Receptors, Immunologic; C045268:beta-glucan receptor; D015054:Zymosan; D019833:Genistein; C497260:Prkcd protein, rat; D011505:Protein-Tyrosine Kinases; D011493:Protein Kinase C; D051745:Protein Kinase C-delta; C058819:calphostin C; C070515:bisindolylmaleimide I; D002118:Calcium