Azidobutyryl clentiazem, a new photoactivatable diltiazem analog, labels benzothiazepine binding sites in the α1 subunit of the skeletal muscle calcium channel

FEBS Letters

Mershon, John¹  Yabana, Hideo¹  Kuniyasu, Akihiko²  Kalasz, Huba¹  Vaghy, Pal L.¹  Schwartz, Arnold¹  Naito, Kazuaki¹  Nakayama, Hitoshi²  Watanabe, Toshiro²  Itagaki, Kiyoshi¹ 

[1] Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0575, USA;Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060, Japan

关键词: [3H]Azidobutyryl clentiazem;    Diltiazem-binding site;    Photoaffinity labeling;    Calcium channel;    Sequence-directed antibody;    ABC;    azidobutyryl clentiazem;    EGTA;    ethylenebis(oxyethylenenitrilo) tetraacetic acid;    HEPES;    N-2-hydroxyethylpiperidine-N'-2-ethanesulfonic acid;    RTT-membranes;    rabbit transverse tubular membranes;    CP;    calcium channel peptide;    WGA;    wheat-germ agglutinin;    SDS;    sodium dodecylsulfate;    PAGE;    polyacrylamide gel electrophoresis;    NEM;    N-ethylmaleimide;    Lys-C;    lysyl endoprotease;   

DOI  :  10.1016/0014-5793(93)80690-V

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

[³H]Azidobutyryl clentiazem, a new photoactivatable diltiazem derivative, has a higher binding affinity than azidobutyryl diltiazem. It can be covalently incorporated into the α₁ subunit of the skeletal muscle calcium channel by UV irradiation, which allows the benzothiazepine binding site to be determined. The photolabeled α₁ subunit and its proteolytic fragments were analyzed with a panel of sequence-directed antibodies. The results suggest that the linker region between segment S5 and S6 of domain IV is involved in benzothiazepine binding. This site is different from the dihydropyridine and verapamil binding sites.

【 授权许可】

Unknown