Cytosolic 5′-Nucleotidase II is a Sensor of Energy Charge and Oxidative Stress: A Possible Function as Metabolic Regulator

Cells

Federico Cividini¹  Francesco Balestri²  Simone Allegrini²  Rossana Pesi²  Marcella Camici²  MariaGrazia Tozzi²  Mercedes Garcia-Gil³  Laura Colombaioni⁴  LarsPetter Jordheim⁵ 

[1] Department of Medicine, University of California, La Jolla, San Diego, CA 92093-0671, USA;Dipartimento di Biologia, Unità di Biochimica, Università di Pisa, Via San Zeno 51, 56127 Pisa, Italy;Dipartimento di Biologia, Unità di Fisiologia Generale, Università di Pisa, Via San Zeno 31, 56127 Pisa, Italy;Istituto di Neuroscienze, CNR, Via Giuseppe Moruzzi 1, 56124 Pisa, Italy;Université Lyon, Université Claude Bernard Lyon 1, INSERM 1052, CNRS 5286, Centre Léon Bérard, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France;

关键词: Cytosolic 5′-nucleotidase II;    NT5C2;    energy charge;    oxidative stress;    AMPK;    ADF;   

DOI  :  10.3390/cells10010182

来源: DOAJ

【 摘 要 】

Cytosolic 5′-nucleotidase II (NT5C2) is a highly regulated enzyme involved in the maintenance of intracellular purine and the pyrimidine compound pool. It dephosphorylates mainly IMP and GMP but is also active on AMP. This enzyme is highly expressed in tumors, and its activity correlates with a high rate of proliferation. In this paper, we show that the recombinant purified NT5C2, in the presence of a physiological concentration of the inhibitor inorganic phosphate, is very sensitive to changes in the adenylate energy charge, especially from 0.4 to 0.9. The enzyme appears to be very sensitive to pro-oxidant conditions; in this regard, the possible involvement of a disulphide bridge (C175-C547) was investigated by using a C547A mutant NT5C2. Two cultured cell models were used to further assess the sensitivity of the enzyme to oxidative stress conditions. NT5C2, differently from other enzyme activities, was inactivated and not rescued by dithiothreitol in a astrocytoma cell line (ADF) incubated with hydrogen peroxide. The incubation of a human lung carcinoma cell line (A549) with 2-deoxyglucose lowered the cell energy charge and impaired the interaction of NT5C2 with the ice protease-activating factor (IPAF), a protein involved in innate immunity and inflammation.

【 授权许可】

Unknown