Reduced extractability of the XPA DNA repair protein in ultraviolet light‐irradiated mammalian cells

FEBS Letters

Solovjeva, Liudmila¹  Svetlova, Maria¹  Nikiforov, Andrey¹  Hanawalt, Philip C.²  Tomilin, Nikolai¹  Pleskach, Nadezhda¹ 

[1] Institute of Cytology of the Russian Academy of Sciences, 194064 St. Petersburg, Russia;Department of Biological Sciences, Stanford University, Stanford, CA 94305-5020, USA

关键词: Nucleotide excision repair;    Xeroderma pigmentosum complementation group A;    Transcription-coupled repair;    Global genome repair;    Ultraviolet irradiation;    NER;    nucleotide excision repair;    TCR;    transcription-coupled repair;    GGR;    global genome repair;    UV;    ultraviolet light;    XPA;    xeroderma pigmentosum complementation group A;    XPB;    xeroderma pigmentosum complementation group B;    XPC;    xeroderma pigmentosum complementation group C;    XPF;    xeroderma pigmentosum complementation group F;    ERCC1;    excision repair complementing protein 1;    PCNA;    proliferating cell nuclear antigen;    CPD;    cyclobutane pyrimidine dimer;    6-4PP;    (6-4) pyrimidine-pyrimidone photoproduct;    PBS;    phosphate-buffered saline;   

DOI  :  10.1016/S0014-5793(99)01592-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The XPA protein is essential for both of the known modes of nucleotide excision repair (NER) in human cells: transcription-coupled repair (TCR) and global genome repair (GGR). In TCR, this protein is thought to be recruited to lesion sites in DNA at which RNA polymerase II is blocked and in GGR, by direct recognition of damages by repair protein complex containing XPC/HR23B or DNA damage-binding protein. However, details of the recruitment of the XPA protein in vivo are unknown. It was shown earlier that a portion of another NER protein, PCNA, which is completely extractable from non-S-phase mammalian nuclei, becomes insoluble after ultraviolet (UV) light irradiation and cannot be extracted by methanol or buffer containing Triton X-100. In the present study, we have found that UV light irradiation of human or Chinese hamster cells leads to decrease of extractability of the XPA protein by Triton X-100. Maximal insolubilization of the XPA protein is observed 1–4 h after irradiation but it is not detectable by 22 h. This effect is dose-dependent for UV light from 2.5 to 15 J/m² and is unaffected by the pre-treatment of cells with sodium butyrate, an inhibitor of histone deacetylation. The UV light-induced insolubilization of the XPA protein was also observed in two lines of Cockayne syndrome complementation group A cells, indicating that the effect is not dependent upon TCR. The results are discussed in relation to possible mechanisms of NER.

【 授权许可】

Unknown