Identification of an intracellular microdomain of the P2X7 receptor that is crucial in basolateral membrane targeting in epithelial cells.

Abstract We investigated membrane targeting of the P2X 7 receptor (P2X 7 R) in polarized epithelial cells using immunofluorescent confocal imaging. The wild-type receptor was targeted to the basolateral membrane, independently of adaptor protein μ1B. Deletion of the majority of the intracellular C-terminus, or the last 26 residues (P570-Y595), conferred targeting of the protein to the apical membrane. Alanine substitution in the microdomain P582-Q587 caused similar apical membrane targeting without major effect on the receptor function and surface expression. Our results show basolateral membrane targeting of the P2X 7 R in epithelial cells and that the intracellular C-terminal microdomain P582-Q587 is crucial in this process. Structured summary MINT- 8055849 : Beta-catenin (uniprotkb: B6V8E6 ) and P2X7R (uniprotkb: Q64663 ) colocalize (MI: 0403 ) by fluorescence microscopy (MI: 0416 )