Human NTH1 physically interacts with p53 and proliferating cell nuclear antigen.
Thymine glycol (Tg) is one of predominant oxidative DNA lesions caused by ionizing radiation and other oxidative stresses. Human NTH1 is a bifunctional enzyme with DNA glycosylase and AP lyase activities and removes Tg as the first step of base excision repair (BER). We have searched for the factors interacting with NTH1 by using a pull-down assay and found that GST-NTH1 fusion protein precipitates proliferating cell nuclear antigen (PCNA) and p53 as well as XPG from human cell-free extracts. GST-NTH1 also bound to recombinant FLAG-tagged XPG, PCNA, and (His)6-tagged p53 proteins, indicating direct protein-protein interaction between those proteins. Furthermore, His-p53 and FLAG-XPG, but not PCNA, stimulated the Tg DNA glycosylase/AP lyase activity of GST-NTH1 or NTH1. These results provide an insight into the positive regulation of BER reaction and also suggest a possible linkage between BER of Tg and other cellular mechanisms.
Oyama
Masaki
M
Laboratory of Molecular Human Genetics, Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa 920-1192, Japan.
Wakasugi
Mitsuo
M
Hama
Takashi
T
Hashidume
Hatsuho
H
Iwakami
Yasutaka
Y
Imai
Rika
R
Hoshino
Sanae
S
Morioka
Hiroshi
H
Ishigaki
Yasuhito
Y
Nikaido
Osamu
O
Matsunaga
Tsukasa
T
D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D004249:DNA Damage; D017931:DNA Primers; D004260:DNA Repair / Q000235:genetics / Q000502:physiology*; D043224:Deoxyribonuclease (Pyrimidine Dimer) / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D018809:Proliferating Cell Nuclear Antigen / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D015183:Restriction Mapping; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*
D017931:DNA Primers; D018809:Proliferating Cell Nuclear Antigen; D011993:Recombinant Fusion Proteins; D016159:Tumor Suppressor Protein p53; D005982:Glutathione Transferase; D043224:Deoxyribonuclease (Pyrimidine Dimer); C468347:NTHL1 protein, human