Spatio-temporal propagation of Ca2+ signals by cyclic ADP-ribose in 3T3 cells stimulated via purinergic P2Y receptors.
The role of cyclic ADP-ribose in the amplification of subcellular and global Ca2+ signaling upon stimulation of P2Y purinergic receptors was studied in 3T3 fibroblasts. Either (1) 3T3 fibroblasts (CD38- cells), (2) 3T3 fibroblasts preloaded by incubation with extracellular cyclic ADP-ribose (cADPR), (3) 3T3 fibroblasts microinjected with ryanodine, or (4) 3T3 fibroblasts transfected to express the ADP-ribosyl cyclase CD38 (CD38+ cells) were used. Both preincubation with cADPR and CD38 expression resulted in comparable intracellular amounts of cyclic ADP-ribose (42.3 +/- 5.2 and 50.5 +/- 8.0 pmol/mg protein). P2Y receptor stimulation of CD38- cells yielded a small increase of intracellular Ca2+ concentration and a much higher Ca2+ signal in CD38-transfected cells, in cADPR-preloaded cells, or in cells microinjected with ryanodine. Confocal Ca2+ imaging revealed that stimulation of ryanodine receptors by cADPR or ryanodine amplified localized pacemaker Ca2+ signals with properties resembling Ca2+ quarks and triggered the propagation of such localized signals from the plasma membrane toward the internal environment, thereby initiating a global Ca2+ wave.
Bruzzone
Santina
S
Department of Experimental Medicine, University of Genova, Italy.
Kunerth
Svenja
S
Zocchi
Elena
E
De Flora
Antonio
A
Guse
Andreas H
AH
D036541:ADP-ribosyl Cyclase / Q000172:deficiency / Q000235:genetics; D051997:ADP-ribosyl Cyclase 1; D000818:Animals; D015703:Antigens, CD / Q000235:genetics; D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling / Q000187:drug effects / Q000502:physiology*; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism*; D036563:Cyclic ADP-Ribose / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism*; D008562:Membrane Glycoproteins; D051379:Mice; D041681:NIH 3T3 Cells; D018048:Receptors, Purinergic P2 / Q000187:drug effects / Q000378:metabolism*; D058472:Receptors, Purinergic P2Y1; D012433:Ryanodine / Q000494:pharmacology; D019837:Ryanodine Receptor Calcium Release Channel / Q000187:drug effects / Q000378:metabolism
D015703:Antigens, CD; D008562:Membrane Glycoproteins; C546383:P2ry1 protein, mouse; D018048:Receptors, Purinergic P2; D058472:Receptors, Purinergic P2Y1; D019837:Ryanodine Receptor Calcium Release Channel; D036563:Cyclic ADP-Ribose; D012433:Ryanodine; D036541:ADP-ribosyl Cyclase; C498155:Cd38 protein, mouse; D051997:ADP-ribosyl Cyclase 1; D002118:Calcium