The nucleoside diphosphate kinase D (NM23-H4) binds the inner mitochondrial membrane with high affinity to cardiolipin and couples nucleotide transfer with respiration.

Abstract

Nucleoside diphosphate kinase (NDPK/Nm23), responsible for intracellular di- and triphosphonucleoside homeostasis, plays multiple roles in cellular energetics, signaling, proliferation, differentiation and tumor invasion. The only human NDPK with a mitochondrial targeting sequence is NDPK-D, the NME4 gene product, which is a peripheral protein of mitochondrial membranes. Subfractionation of rat liver and HEK 293 cell mitochondria revealed that NDPK-D is essentially bound to the inner membrane. Surface plasmon resonance analysis of the interaction using recombinant NDPK-D and model liposomes showed that NDPK-D interacts electrostatically with anionic phospholipids, with highest affinity observed for cardiolipin. Mutation of the central arginine (Arg-90) in a surface-exposed basic RRK motif unique to NDPK-D strongly reduced interaction with anionic phospholipids. Due to its symmetrical hexameric structure, NDPK-D was able to cross-link anionic phospholipid-containing liposomes, suggesting that NDPK-D could promote intermembrane contacts. Latency assays with isolated mitochondria and antibody binding to mitoplasts indicated a dual orientation for NDPK-D. In HeLa cells, stable expression of wild type but not of the R90D mutant led to membrane-bound enzyme in vivo. Respiration was significantly stimulated by the NDPK substrate TDP in mitochondria containing wild-type NDPK-D, but not in those expressing the R90D mutant, which is catalytically equally active. This indicates local ADP regeneration in the mitochondrial intermembrane space and a tight functional coupling of NDPK-D with oxidative phosphorylation that depends on its membrane-bound state.

• Authors: Malgorzata Tokarska-Schlattner, Mathieu Boissan, Annie Munier, Caroline Borot, Christiane Mailleau, Oliver Speer, Uwe Schlattner, Marie-Lise Lacombe
• Journal: The Journal of biological chemistry (J Biol Chem) Vol. 283 Issue 38 Pg. 26198-207 (Sep 19 2008) ISSN: 0021-9258 [Print] United States
• PMID: 18635542 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Cardiolipins
• NM23 Nucleoside Diphosphate Kinases
• NME1 protein, human

Topics

• Amino Acid Sequence
• Animals
• Cardiolipins (chemistry)
• Humans
• Intracellular Membranes (metabolism)
• Male
• Mitochondria (metabolism)
• Mitochondria, Liver (metabolism)
• Molecular Sequence Data
• NM23 Nucleoside Diphosphate Kinases (chemistry, genetics, physiology)
• Oxygen Consumption
• Rats
• Rats, Wistar
• Sequence Homology, Amino Acid