Basal activation of the P2X7 ATP receptor elevates mitochondrial calcium and potential, increases cellular ATP levels, and promotes serum-independent growth |
| |
Authors: | Adinolfi Elena Callegari Maria Giulia Ferrari Davide Bolognesi Chiara Minelli Mattia Wieckowski Mariusz R Pinton Paolo Rizzuto Rosario Di Virgilio Francesco |
| |
Affiliation: | Department of Experimental and Diagnostic Medicine, Section of General Pathology, and Interdisciplinary Center for the Study of Inflammation, University of Ferrara, 44100 Ferrara, Italy. |
| |
Abstract: | P2X7 is a bifunctional receptor (P2X7R) for extracellular ATP that, depending on the level of activation, forms a cation-selective channel or a large conductance nonselective pore. The P2X7R has a strong proapoptotic activity but can also support growth. Here, we describe the mechanism involved in growth stimulation. Transfection of P2X7R increases resting mitochondrial potential (delta psi(mt)), basal mitochondrial Ca2+ (Ca2+]mt), intracellular ATP content, and confers ability to grow in the absence of serum. These changes require a full pore-forming function, because they are abolished in cells transfected with a mutated P2X7R that retains channel activity but cannot form the nonselective pore, and depend on an autocrine/paracrine tonic stimulation by secreted ATP. On the other hand, sustained stimulation of P2X7R causes a delta psi(mt) drop, a large increase in Ca2+]mt, mitochondrial fragmentation, and cell death. These findings reveal a hitherto undescribed mechanism for growth stimulation by a plasma membrane pore. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|