title: Regulation of CA(v)3.2 Ca2+ channel activity by protein tyrosine phosphorylation.
abstract: Calcium entry through Cav3.2 Ca2+ channels plays essential roles for various physiological events including thalamic oscillation, muscle contraction, hormone secretion, and sperm acrosomal reaction. In this study, we examined how protein tyrosine phosphatases or protein tyrosine kinases affect Cav3.2 Ca2+ channels reconstituted in Xenopus oocytes. We found that Cav3.2 channel activity was reduced by 25% in response to phenylarsine oxide (tyrosine phosphatase inhibitor), whereas it was augmented by 19% in response to Tyr A47 or herbimycin A (tyrosine kinase inhibitors). However, other biophysical properties of Cav3.2 currents were not significantly changed by the drugs. These results imply that Cav3.2 channel activity is capable of being increased by activation of tyrosine phosphatases, but is decreased by activation of tyrosine kinases.
authors.affiliation: Department of Life Science, Sogang University, Seoul 121-742, Korea.
authors.forename: Sung-Un
authors.initials: SU
authors.lastname: Huh
authors.forename: Ho-Won
authors.initials: HW
authors.lastname: Kang
authors.forename: Jin-Yong
authors.initials: JY
authors.lastname: Park
authors.forename: Jung-Ha
authors.initials: JH
authors.lastname: Lee
mesh_terms: D000818:Animals; D001152:Arsenicals / Q000494:pharmacology; D020747:Calcium Channels, T-Type / Q000235:genetics / Q000378:metabolism*; D004594:Electrophysiology / Q000379:methods; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D009865:Oocytes / Q000201:enzymology / Q000378:metabolism; D010766:Phosphorylation; D017027:Protein Tyrosine Phosphatases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism*; D014981:Xenopus / Q000378:metabolism; D029867:Xenopus Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D001152:Arsenicals; C479952:CACNA1H protein, human; D020747:Calcium Channels, T-Type; D004791:Enzyme Inhibitors; D029867:Xenopus Proteins; C029341:oxophenylarsine; D014443:Tyrosine; D011505:Protein-Tyrosine Kinases; D017027:Protein Tyrosine Phosphatases