Premium
The intracellular tyrosine residues of the ATP‐gated P2X 1 ion channel are essential for its function
Author(s) -
Toth-Zsamboki Emese,
Oury Cecile,
Watanabe Hiroyuki,
Nilius Bernd,
Vermylen Jos,
Hoylaerts Marc F
Publication year - 2002
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/s0014-5793(02)02987-3
Subject(s) - hek 293 cells , intracellular , tyrosine , transfection , mutant , phosphorylation , tyrosine phosphorylation , ion channel , microbiology and biotechnology , chemistry , blot , biochemistry , biology , gene , receptor
The four highly conserved intracellular tyrosine residues of the P2X 1 ion channel were mutated into phenylalanine. Simultaneous electrophysiological and calcium measurements in transfected human embryonic kidney (HEK 293) cells indicated that Y362F and Y370F mutants were non‐functional, despite their proper plasma membrane expression. The Y16F and Y363F mutants retained 2.2% and 26% of the wild‐type P2X 1 activity, respectively. However, no tyrosine phosphorylation was detected on Western blots of P2X 1 immunoprecipitates derived either from HEK 293 cell lysates or from human platelets, expressing P2X 1 endogenously. Thus, Y16, Y362, Y363 and Y370 are required for the appropriate three‐dimensional structure and function of the intracellular P2X 1 domains.