Differentiation of answer of glioma C6 cells to SERCA pump inhibitors by actin disorganization.
Capacitative calcium entry, usually evoked by receptor-ligand binding, may be also studied in the model system of calcium release after SERCA pump inhibition. We have previously found that disorganization of actin cytoskeleton has no effect on calcium influx into glioma C6 cells after thapsigargin administration [Biochem. Biophys. Res. Commun. 296 (2002) 484]. In the present work we show that the effect of other SERCA pump inhibitors depends on the endoplasmic reticulum distribution in a cell. Changing this distribution leads to changes in calcium release from ER stores. Intensity of calcium influx in the capacitative phase of cell answer does not depend on actin cytoskeleton state; however, administration of cytochalasin D significantly slows down signal build-up. While cyclopiazonic acid acts very similarly to thapsigargin, cytoskeleton disorganization leads to rise of calcium signal after administration of 2,5-di-(t-butyl)-1,4-benzohydroquinone. This effect may be caused by specific binding of this inhibitor to SERCA3 isoform of pump protein only.
Supłat
Dorota
D
Laboratory of Signal Transduction, Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Str., 02-093 Warsaw, Poland.
Targos
Berenika
B
Sabała
Paweł
P
Barańska
Jolanta
J
Pomorski
Paweł
P
D008841:Actin Cytoskeleton / Q000378:metabolism / Q000648:ultrastructure; D000199:Actins / Q000378:metabolism* / Q000648:ultrastructure*; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D045744:Cell Line, Tumor; D015638:Cytochalasin D / Q000494:pharmacology; D004721:Endoplasmic Reticulum / Q000378:metabolism / Q000648:ultrastructure; D005910:Glioma / Q000378:metabolism* / Q000473:pathology*; D051381:Rats; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases; D019284:Thapsigargin / Q000494:pharmacology
D000199:Actins; C506951:Atp2a3 protein, rat; D015638:Cytochalasin D; D019284:Thapsigargin; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases; D000252:Calcium-Transporting ATPases; D002118:Calcium