title: The spatiotemporal relationship between local Ca(2+) signaling and P2X2R-activated membrane blebbing.
abstract: Mammalian P2X receptors (P2XRs), a family of seven ionotropic purinergic receptors, function as ion channels modulating diverse cellular processes such as secretion, apoptosis and proliferation in response to extracellular ATP. Previously, it was shown that upon ATP stimulus, the P2X7 receptor (a member of P2XR family) triggers plasma membrane (PM) blebbing in HEK293 cells. In this study, we demonstrate that this phenomenon extends to another member of the P2XR family-P2X2 receptor (P2X2R). Similar to P2X7 receptor, P2X2R blebbing is dependent on Ca(2+)-calmodulin and ROCK-I. To elucidate the spatiotemporal relationship between Ca(2+) signaling and blebbing, protein biosensors and switches were used to image and generate Ca(2+) signals, respectively, while observing PM blebbing in cells. Blebbing cannot be initiated by Ca(2+) influx from the endoplasmic reticulum or by Ca(2+) transport across the PM by other Ca(2+) channels. To trigger blebbing, it is necessary for Ca(2+) to enter specifically through the P2X2R. Lastly, a local Ca(2+) signal near a fragment that encodes the intracellular P2X2R C-terminus tail is sufficient to trigger blebbing.
authors: Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON, Canada M5S 3G9.
authors: Anam
authors: A
authors: Qudrat
authors: Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON, Canada M5S 3G9.
authors: Jae Ik
authors: JI
authors: Kim
authors: Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON, Canada M5S 3G9; Edward S. Rogers, Sr. Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Circle, Toronto, ON, Canada M5S 3G4. Electronic address: kevin.truong@utoronto.ca.
authors: Kevin
authors: K
authors: Truong
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling; D002462:Cell Membrane / Q000378:metabolism*; D002478:Cells, Cultured; D003600:Cytosol / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D058486:Receptors, Purinergic P2X7 / Q000378:metabolism*
chemical_list: D058486:Receptors, Purinergic P2X7; D000255:Adenosine Triphosphate; D002118:Calcium
keywords: Ca(2+) signaling; P2X2Rs; Plasma membrane blebbing