Ouabain‐ and Ca2+‐sensitive ATPase activity of chimeric Na‐ and Ca‐pump molecules

FEBS Letters

Boyd, Kimberly L.¹  Luckie, Douglas B.¹  Takeyasu, Kunio¹ 

[1] Department of Physiology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA

关键词: Na+;    K+-ATPase;    Ca2+-ATPase;    Ouabain;    Chimeric molecule;    Chicken;    ATPase;    adenosine-tri-phosphatase;    FITC;    fluorescein-isothiocyanate;    FSBA;    5′-(p-fluorosulfonyl)benzoyl-adenosine;    PM;    plasma membrane;    SR;    sarcoplasmic reticulum;    TRITC;    tetramethylrhodamine;   

DOI  :  10.1016/0014-5793(91)80400-W

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Chimeric ion-pumps, consisting of the N-terminal of the α₁-subunit of the ouabain-sensitive chicken Na⁺, K⁺-ATPase and the C-terminal of the sarcoplasmic reticulum Ca²⁺-ATPase, were expressed in ouabain-insensitive mouse L cells. These chimeric molecules exhibited ouabain-sensitive ATPase activity very similar to that of the wild-type chicken Na⁺ K⁺-ATPase. This ATPase activity could be stimulated by adding Ca²⁺ to the assay system. These results suggest that the sites for ouabain-inhibition are restricted to the N-terminal of the Na-pump, and the C-terminal of the Ca-pump interacts with Ca³⁺.

【 授权许可】

Unknown