title: Crystal structure, biochemical and cellular activities demonstrate separate functions of MTH1 and MTH2.
abstract: Deregulated redox metabolism in cancer leads to oxidative damage to cellular components including deoxyribonucleoside triphosphates (dNTPs). Targeting dNTP pool sanitizing enzymes, such as MTH1, is a highly promising anticancer strategy. The MTH2 protein, known as NUDT15, is described as the second human homologue of bacterial MutT with 8-oxo-dGTPase activity. We present the first NUDT15 crystal structure and demonstrate that NUDT15 prefers other nucleotide substrates over 8-oxo-dGTP. Key structural features are identified that explain different substrate preferences for NUDT15 and MTH1. We find that depletion of NUDT15 has no effect on incorporation of 8-oxo-dGTP into DNA and does not impact cancer cell survival in cell lines tested. NUDT17 and NUDT18 were also profiled and found to have far less activity than MTH1 against oxidized nucleotides. We show that NUDT15 is not a biologically relevant 8-oxo-dGTPase, and that MTH1 is the most prominent sanitizer of the cellular dNTP pool known to date.
authors.affiliation: Department of Biochemistry and Biophysics, Stockholm University, S-106 91 Stockholm, Sweden.
authors.forename: Megan
authors.initials: M
authors.lastname: Carter
authors.affiliation: Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-171 21 Stockholm, Sweden.
authors.forename: Ann-Sofie
authors.initials: AS
authors.lastname: Jemth
authors.affiliation: Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-171 21 Stockholm, Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Hagenkort
authors.affiliation: Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-171 21 Stockholm, Sweden.
authors.forename: Brent D G
authors.initials: BD
authors.lastname: Page
authors.affiliation: Department of Biochemistry and Biophysics, Stockholm University, S-106 91 Stockholm, Sweden.
authors.forename: Robert
authors.initials: R
authors.lastname: Gustafsson
authors.affiliation: Department of Biochemistry and Biophysics, Stockholm University, S-106 91 Stockholm, Sweden.
authors.forename: Julia J
authors.initials: JJ
authors.lastname: Griese
authors.affiliation: Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-171 21 Stockholm, Sweden.
authors.forename: Helge
authors.initials: H
authors.lastname: Gad
authors.affiliation: Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-171 21 Stockholm, Sweden.
authors.forename: Nicholas C K
authors.initials: NC
authors.lastname: Valerie
authors.affiliation: Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-171 21 Stockholm, Sweden.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Desroses
authors.affiliation: Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-171 21 Stockholm, Sweden.
authors.forename: Johan
authors.initials: J
authors.lastname: Boström
authors.affiliation: Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-171 21 Stockholm, Sweden.
authors.forename: Ulrika
authors.initials: U
authors.lastname: Warpman Berglund
authors.affiliation: Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-171 21 Stockholm, Sweden.
authors.forename: Thomas
authors.initials: T
authors.lastname: Helleday
authors.affiliation: Department of Biochemistry and Biophysics, Stockholm University, S-106 91 Stockholm, Sweden.
authors.forename: Pål
authors.initials: P
authors.lastname: Stenmark
mesh_terms: D015153:Blotting, Western; D045744:Cell Line, Tumor; D002470:Cell Survival; D003460:Crystallization; D045643:DNA Repair Enzymes / Q000378:metabolism*; D003848:Deoxyguanine Nucleotides / Q000378:metabolism*; D003854:Deoxyribonucleotides / Q000378:metabolism*; D045325:HCT116 Cells; D006367:HeLa Cells; D006801:Humans; D061986:MCF-7 Cells; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D011755:Pyrophosphatases / Q000737:chemistry / Q000378:metabolism*; D013379:Substrate Specificity; D000096964:Nudix Hydrolases
chemical_list: D045643:DNA Repair Enzymes; D003848:Deoxyguanine Nucleotides; D003854:Deoxyribonucleotides; D010744:Phosphoric Monoester Hydrolases; D011755:Pyrophosphatases; C078206:8-oxodeoxyguanosine triphosphate; C543721:NUDT15 protein, human; D000096964:Nudix Hydrolases; C078207:8-oxodGTPase