HSP90 Regulation of P2X7 Receptor Function Requires an Intact Cytoplasmic C-Terminus.
P2X7 receptors (P2X7Rs) are ATP-gated ion channels that display the unusual property of current facilitation during long applications of agonists. Here we show that facilitation disappears in chimeric P2X7Rs containing the C-terminus of the P2X2 receptor (P2X2R), and in a truncated P2X7R missing the cysteine-rich domain of the C-terminus. The chimeric and truncated receptors also show an apparent decreased permeability to N-methyl-d-glucamine(+) (NMDG(+)). The effects of genetic modification of the C-terminus on NMDG(+) permeability were mimicked by preapplication of the HSP90 antagonist geldanamycin to the wild-type receptor. Further, the geldanamycin decreased the shift in the reversal potential of the ATP-gated current measured under bi-ionic NMDG(+)/Na(+) condition without affecting the ability of the long application of agonist to facilitate current amplitude. Taken together, the results suggest that HSP90 may be essential for stabilization and function of P2X7Rs through an action on the cysteine-rich domain of the cytoplasmic the C-terminus.
Department of Drug Informatics, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan (K.M.); Department of Neurophysiology (T.O., S.S., Y.N., T.F., Y.S., S.U.) and Research Center for Child Mental Development (T.O., S.S., S.U.), Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan; Department of Biomedical Sciences, Hirosaki University Graduate School of Health Sciences, Hirosaki, Aomori, Japan (J.Y.); and Department of Pharmacology and Physiology, and The Center for Neuroscience, Saint Louis University School of Medicine, St. Louis, Missouri (T.M.E.) migitak@fukuoka-u.ac.jp.
Keisuke
K
Migita
Department of Drug Informatics, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan (K.M.); Department of Neurophysiology (T.O., S.S., Y.N., T.F., Y.S., S.U.) and Research Center for Child Mental Development (T.O., S.S., S.U.), Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan; Department of Biomedical Sciences, Hirosaki University Graduate School of Health Sciences, Hirosaki, Aomori, Japan (J.Y.); and Department of Pharmacology and Physiology, and The Center for Neuroscience, Saint Louis University School of Medicine, St. Louis, Missouri (T.M.E.).
Taku
T
Ozaki
Department of Drug Informatics, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan (K.M.); Department of Neurophysiology (T.O., S.S., Y.N., T.F., Y.S., S.U.) and Research Center for Child Mental Development (T.O., S.S., S.U.), Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan; Department of Biomedical Sciences, Hirosaki University Graduate School of Health Sciences, Hirosaki, Aomori, Japan (J.Y.); and Department of Pharmacology and Physiology, and The Center for Neuroscience, Saint Louis University School of Medicine, St. Louis, Missouri (T.M.E.).
Shuji
S
Shimoyama
Department of Drug Informatics, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan (K.M.); Department of Neurophysiology (T.O., S.S., Y.N., T.F., Y.S., S.U.) and Research Center for Child Mental Development (T.O., S.S., S.U.), Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan; Department of Biomedical Sciences, Hirosaki University Graduate School of Health Sciences, Hirosaki, Aomori, Japan (J.Y.); and Department of Pharmacology and Physiology, and The Center for Neuroscience, Saint Louis University School of Medicine, St. Louis, Missouri (T.M.E.).
Junko
J
Yamada
Department of Drug Informatics, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan (K.M.); Department of Neurophysiology (T.O., S.S., Y.N., T.F., Y.S., S.U.) and Research Center for Child Mental Development (T.O., S.S., S.U.), Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan; Department of Biomedical Sciences, Hirosaki University Graduate School of Health Sciences, Hirosaki, Aomori, Japan (J.Y.); and Department of Pharmacology and Physiology, and The Center for Neuroscience, Saint Louis University School of Medicine, St. Louis, Missouri (T.M.E.).
Yoshikazu
Y
Nikaido
Department of Drug Informatics, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan (K.M.); Department of Neurophysiology (T.O., S.S., Y.N., T.F., Y.S., S.U.) and Research Center for Child Mental Development (T.O., S.S., S.U.), Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan; Department of Biomedical Sciences, Hirosaki University Graduate School of Health Sciences, Hirosaki, Aomori, Japan (J.Y.); and Department of Pharmacology and Physiology, and The Center for Neuroscience, Saint Louis University School of Medicine, St. Louis, Missouri (T.M.E.).
Tomonori
T
Furukawa
Department of Drug Informatics, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan (K.M.); Department of Neurophysiology (T.O., S.S., Y.N., T.F., Y.S., S.U.) and Research Center for Child Mental Development (T.O., S.S., S.U.), Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan; Department of Biomedical Sciences, Hirosaki University Graduate School of Health Sciences, Hirosaki, Aomori, Japan (J.Y.); and Department of Pharmacology and Physiology, and The Center for Neuroscience, Saint Louis University School of Medicine, St. Louis, Missouri (T.M.E.).
Yuko
Y
Shiba
Department of Drug Informatics, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan (K.M.); Department of Neurophysiology (T.O., S.S., Y.N., T.F., Y.S., S.U.) and Research Center for Child Mental Development (T.O., S.S., S.U.), Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan; Department of Biomedical Sciences, Hirosaki University Graduate School of Health Sciences, Hirosaki, Aomori, Japan (J.Y.); and Department of Pharmacology and Physiology, and The Center for Neuroscience, Saint Louis University School of Medicine, St. Louis, Missouri (T.M.E.).
Terrance M
TM
Egan
Department of Drug Informatics, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan (K.M.); Department of Neurophysiology (T.O., S.S., Y.N., T.F., Y.S., S.U.) and Research Center for Child Mental Development (T.O., S.S., S.U.), Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan; Department of Biomedical Sciences, Hirosaki University Graduate School of Health Sciences, Hirosaki, Aomori, Japan (J.Y.); and Department of Pharmacology and Physiology, and The Center for Neuroscience, Saint Louis University School of Medicine, St. Louis, Missouri (T.M.E.).
Shinya
S
Ueno
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D016227:Benzoquinones / Q000494:pharmacology; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D002463:Cell Membrane Permeability / Q000187:drug effects; D003593:Cytoplasm / Q000378:metabolism*; D057809:HEK293 Cells; D018841:HSP90 Heat-Shock Proteins / Q000378:metabolism*; D006801:Humans; D015640:Ion Channel Gating / Q000187:drug effects; D047029:Lactams, Macrocyclic / Q000494:pharmacology; D008536:Meglumine / Q000378:metabolism; D050505:Mutant Proteins / Q000378:metabolism; D011485:Protein Binding / Q000187:drug effects; D000072417:Protein Domains; D051381:Rats; D058486:Receptors, Purinergic P2X7 / Q000737:chemistry* / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D013329:Structure-Activity Relationship
D016227:Benzoquinones; D018841:HSP90 Heat-Shock Proteins; D047029:Lactams, Macrocyclic; D050505:Mutant Proteins; D058486:Receptors, Purinergic P2X7; D011994:Recombinant Proteins; D008536:Meglumine; D000255:Adenosine Triphosphate; C001277:geldanamycin