Functional studies of the effect of NO donor on human CLCN1 polymorphism/mutants expressed in Xenopus laevis oocytes.
In this study, we investigated the effect of NO donor, diethylamine/nitric oxide (DEA/NO), on the electrophysiological behavior of human skeletal muscle chloride channel (CLCN1). The wild-type and variants of CLCN1, including one polymorphism (P727L) and four mutants (T631I, D644G, G482R, and S471F), were expressed in Xenopus oocytes and the ionic current was measured by two-electrode voltage-clamp method. Our results revealed that there is no significant difference in the current-voltage relationships and half-voltage values of open probability between wild-type and variants of CLCN1 except for G482R. Application of the DEA-NO (0.1mM) significantly increases the channel conductance of wild-type, T631I, D644G, and S471F, but not P727L. This indicates that P727L polymorphism causes loss of sensitivity of CLCN1 to the DEA/NO treatment, which could be due to a conformational change caused by proline substitution. The data suggest that the polymorphic changes may affect the function of CLCN1 in response to the treatment of chemical compounds.
Lin
Min-Jon
MJ
Department of Biomedical Sciences, Chung Shan Medical University, No. 110, Sec 1, Chien-Kuo N. Road, Taichung 402, Taiwan, ROC.
Huang
Ren-Yu
RY
Pan
Huichin
H
Hsiao
Kuang-Ming
KM
D000818:Animals; D002478:Cells, Cultured; D018118:Chloride Channels / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D004048:Diethylamines / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D015640:Ion Channel Gating / Q000187:drug effects / Q000502:physiology*; D016297:Mutagenesis, Site-Directed; D020030:Nitric Oxide Donors / Q000008:administration & dosage*; D009865:Oocytes / Q000187:drug effects / Q000502:physiology*; D011110:Polymorphism, Genetic; D013329:Structure-Activity Relationship; D014982:Xenopus laevis
C086321:CLC-1 channel; D018118:Chloride Channels; D004048:Diethylamines; D020030:Nitric Oxide Donors; C034281:diethylamine