Functional Analysis of the Disulfide Bonds of Na+/K+-ATPase β-subunit by Site-directed Mutagenesis

  • M. Kawamura
  • S. Noguchi
  • S. Ueno
  • M. Kusaba
  • K. Takeda

Abstract

The ion transporting Na+/K+-ATPase of animal plasma membranes consists of the catalytic α- and the glycosylated β-subunit All the functional roles in the catalytic activity of the enzyme so far known belong to the α-subunit, whereas those of the β-subunit remain still unknown. However, the β-subunit has been revealed to play important roles in the biogenesis of the enzyme. It acts as a stabilizer of the nascent α-subunit within the endoplasmic reticulum [9, 10] and takes part in targeting the resulting αβ -complex to the plasma membrane [2,12].

Keywords

Cysteine Electrophoresis Serine Trypsin Polyacrylamide 

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Copyright information

© Dietrich Steinkopff Verlag GmbH & Co. KG, Darmstadt 1994

Authors and Affiliations

  • M. Kawamura
    • 2
  • S. Noguchi
    • 1
  • S. Ueno
    • 2
  • M. Kusaba
    • 1
  • K. Takeda
    • 2
  1. 1.Department of Biochemical Engineering and Science, Faculty of Computer Science and Systems EngineeringKyushu Institute of TechnologyIizuka, 820Japan
  2. 2.Faculty of MedicineUniversity of Occupational and Environmental HealthKitakyushu, 807Japan

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