The P2X7/P2X4 interaction shapes the purinergic response in murine macrophages

• Published in: Biochemical and biophysical research communications Vol. 467; no. 3; pp. 484 - 490
• Main Authors: Pérez-Flores, Gabriela, Lévesque, Sébastien A., Pacheco, Jonathan, Vaca, Luis, Lacroix, Steve, Pérez-Cornejo, Patricia, Arreola, Jorge
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 20-11-2015
• Subjects: Animals; Cell death; Fluorescence Resonance Energy Transfer; Fluorescent Dyes; FRET; HEK293 Cells; Humans; IL-1β; Macrophages - metabolism; Mice; Mice, Inbred C57BL; Mice, Knockout; P2X4; P2X7; Patch clamp; Receptors, Purinergic P2X4 - metabolism; Receptors, Purinergic P2X7 - metabolism; YFP; P2X7; Bz-ATP; Cell death; Patch clamp; FRET; P2X4; IL-1β; CFP; LPS; PCR
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2015.10.025

The ATP-gated P2X4 and P2X7 receptors are cation channels, co-expressed in excitable and non-excitable cells and play important roles in pain, bone development, cytokine release and cell death. Although these receptors interact the interacting domains are unknown and the functional consequences of this interaction remain unclear. Here we show by co-immunoprecipitation that P2X4 interacts with the C-terminus of P2X7 and by fluorescence resonance energy transfer experiments that this receptor–receptor interaction is driven by ATP. Furthermore, disrupting the ATP-driven interaction by knocking-out P2X4R provoked an attenuation of P2X7-induced cell death, dye uptake and IL-1β release in macrophages. Thus, P2X7 interacts with P2X4 via its C-terminus and disrupting the P2X7/P2X4 interaction hinders physiological responses in immune cells.
•In unstimulated HEK-293 cells, P2X4 and P2X7 associate via the C-terminus of P2X7.•5 mM ATP activates P2X7 and promotes a closer interaction between P2X4 and P2X7.•Impairing this interaction affects macrophage death, dye uptake and IL-1β release.