title: Deoxyribonucleoside triphosphate pools and growth of glutathione-depleted 3T6 mouse fibroblasts.
abstract: Buthionine sulfoximine (BSO) selectively blocks g-glutamylcysteine synthetase and thereby depletes cells of glutathione (GSH). In cultures of exponentially growing 3T6 mouse fibroblasts, 0.1 mM BSO rapidly stopped GSH synthesis after treatment for 12 hours. The GSH-depleted cells grew as well as control 3T6 cells with no decrease in DNA synthesis. Furthermore, the pools of deoxyribonucleoside triphosphates (dNTPs), typically tightly regulated in cultured cells, did not change in size. Ribonucleotide reductase catalyzes the reduction of all four ribonucleotides and occupies a key position in dNTP regulation. Our data suggest that the GSH-glutaredoxin (a GSH-dependent disulfide-oxidoreductase) system is not the sole/major hydrogen carrier from NADPH for the reduction of ribonucleoside diphosphates by ribonucleotide reductase.
authors.affiliation: Department of Medical Biochemistry and Biophysics, Medical Nobel Institute for Biochemistry I, Karolinska Institute, Stockholm, Sweden.
authors.forename: G
authors.initials: G
authors.lastname: Spyrou
authors.forename: A
authors.initials: A
authors.lastname: Holmgren
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites / Q000235:genetics; D019328:Buthionine Sulfoximine; D002455:Cell Division / Q000187:drug effects / Q000502:physiology*; D002460:Cell Line; D004247:DNA / Q000096:biosynthesis; D003854:Deoxyribonucleotides / Q000378:metabolism*; D004579:Electron Transport; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005347:Fibroblasts; D005721:Glutamate-Cysteine Ligase / Q000037:antagonists & inhibitors; D054477:Glutaredoxins; D005978:Glutathione / Q000378:metabolism*; D008717:Methionine Sulfoximine / Q000031:analogs & derivatives / Q000494:pharmacology; D051379:Mice; D008969:Molecular Sequence Data; D009249:NADP / Q000378:metabolism; D010084:Oxidation-Reduction; D010088:Oxidoreductases; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D013879:Thioredoxins / Q000235:genetics / Q000378:metabolism
chemical_list: D003854:Deoxyribonucleotides; D004791:Enzyme Inhibitors; D054477:Glutaredoxins; D011506:Proteins; D008717:Methionine Sulfoximine; D019328:Buthionine Sulfoximine; D013879:Thioredoxins; D009249:NADP; D004247:DNA; D010088:Oxidoreductases; D005721:Glutamate-Cysteine Ligase; D005978:Glutathione