Identification of cisplatin-binding sites on the large cytoplasmic loop of the Na+/K+-ATPase

J Enzyme Inhib Med Chem. 2018 Dec;33(1):701-706. doi: 10.1080/14756366.2018.1445735.

Abstract

Cisplatin is the most widely used chemotherapeutic drug for the treatment of various types of cancer; however, its administration brings also numerous side effects. It was demonstrated that cisplatin can inhibit the Na+/K+-ATPase (NKA), which can explain a large part of the adverse effects. In this study, we have identified five cysteinyl residues (C452, C456, C457, C577, and C656) as the cisplatin binding sites on the cytoplasmic loop connecting transmembrane helices 4 and 5 (C45), using site-directed mutagenesis and mass spectrometry experiments. The identified residues are known to be susceptible to glutathionylation indicating their involvement in a common regulatory mechanism.

Keywords: C45 loop; Na+/K+-ATPase; binding site; cisplatin; cysteine mutants; sodium pump.

MeSH terms

  • Animals
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / pharmacology*
  • Binding Sites / drug effects
  • Cisplatin / chemistry
  • Cisplatin / pharmacology*
  • Cysteine / antagonists & inhibitors*
  • Cysteine / metabolism
  • Cytoplasm / drug effects*
  • Cytoplasm / metabolism
  • Mass Spectrometry
  • Mice
  • Molecular Dynamics Simulation
  • Mutagenesis, Site-Directed
  • Sodium-Potassium-Exchanging ATPase / antagonists & inhibitors*
  • Sodium-Potassium-Exchanging ATPase / genetics
  • Sodium-Potassium-Exchanging ATPase / metabolism

Substances

  • Antineoplastic Agents
  • Sodium-Potassium-Exchanging ATPase
  • Cysteine
  • Cisplatin

Grants and funding

This work was supported by grant LO1024 from the National Programme of Sustainability I, Ministry of Schools, Youth and Sports, Czech Republic, and by Endowment Fund of Palacky University, Olomouc.