[en] In this study, we mutated 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.
Disciplines :
Biochemistry, biophysics & molecular biology
Author, co-author :
Oury, Cécile ; Université de Liège - ULiège > Département des sciences biomédicales et précliniques > GIGA-R : Génétique humaine
Toth-Zsamboki, Emese; Katholieke Universiteit Leuven - KUL > Molecular and Cellular Medicine > CMVB
Watanabe, Hiroyuki; Katholieke Universiteit Leuven - KUL > Molecular and Cellular Medicine > Laboratory of Physiology
Nilius, Bernd; Katholieke Universiteit Leuven - KUL > Molecular and Cellular Medicine > Laboratory of Physiology
Vermylen, Jos; Katholieke Universiteit Leuven - KUL > Molecular and Cellular Medicine > CMVB
Hoylaerts, Marc F; Katholieke Universiteit Leuven - KUL > Molecular and Cellular Medicine > CMVB
Language :
English
Title :
The intracellular tyrosine residues of the ATP-gated P2X(1) ion channel are essential for its function.
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