Kinases, intracellular calcium, and apolipophorin-III influence the adhesion of larval hemocytes of the lepidopterous insect, Galleria mellonella.
Based on the results from the use of selective inhibitors and activators, active protein kinase A, protein tyrosine kinase, and protein kinase C (PKC) isoforms decreased the adhesion of larval Galleria mellonella hemocytes to glass slides. The protein kinase A inhibitor at all concentrations increased granular cell adhesion only whereas protein tyrosine kinase elevated both granular and plasmatocyte attachment at the lowest concentration. Active, Ca(2+)- and lipid-dependent PKC isoforms limited plasmatocyte and granular cell adhesion whereas PKC that was inhibited by selected compounds (with differed modes of PKC inhibition) enhanced hemocyte attachment. The granular cells were more sensitive to the PKC inhibitors than were plasmatocytes. Phospholipase C and its diacylglyceride product were necessary to reduce hemocyte adhesion and maintain PKC activity. Extracellular Ca(2+), possibly transported through L-channels, was required for plasmatocyte attachment. In contrast, lowering the levels of cytosolic Ca(2+) was associated with decreased PKC activity and was required for hemocyte adhesion.
Zakarian
Robert J
RJ
Department of Natural Resource Sciences, McGill University, Montreal, Canada.
Dunphy
Gary B
GB
Rau
Manfred E
ME
Albert
Paul J
PJ
D000818:Animals; D001053:Apolipoproteins / Q000378:metabolism* / Q000494:pharmacology; D002118:Calcium / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D002448:Cell Adhesion / Q000502:physiology; D004075:Diglycerides / Q000737:chemistry / Q000494:pharmacology; D004347:Drug Interactions; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006434:Hemocytes / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D007424:Intracellular Fluid / Q000737:chemistry; D007527:Isoenzymes / Q000037:antagonists & inhibitors / Q000378:metabolism / Q000494:pharmacology; D007814:Larva / Q000378:metabolism; D007915:Lepidoptera / Q000201:enzymology / Q000378:metabolism*; D010770:Phosphotransferases / Q000037:antagonists & inhibitors / Q000145:classification / Q000378:metabolism* / Q000494:pharmacology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D010738:Type C Phospholipases / Q000037:antagonists & inhibitors / Q000494:pharmacology
D001053:Apolipoproteins; D004075:Diglycerides; D004791:Enzyme Inhibitors; D007527:Isoenzymes; C042470:apolipophorin III; D010770:Phosphotransferases; D010738:Type C Phospholipases; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium