[PDF][PDF] SIRT1 regulates UV-induced DNA repair through deacetylating XPA

W Fan, J Luo - Molecular cell, 2010 - cell.com
W Fan, J Luo
Molecular cell, 2010cell.com
Summary SIRT1, a NAD+-dependent histone deacetylase, plays crucial roles in multiple
biological processes including gene transcription, cellular metabolism, stress response, and
tumorigenesis. Xeroderma pigmentosum group A (XPA) is a core nucleotide excision repair
(NER) factor essential for NER process. Here we show that SIRT1 plays an important role in
the regulation of NER pathway. Downregulation of SIRT1 significantly sensitizes cells to UV
irradiation. SIRT1 interacts with XPA, and the interaction is enhanced after UV irradiation …
Summary
SIRT1, a NAD+-dependent histone deacetylase, plays crucial roles in multiple biological processes including gene transcription, cellular metabolism, stress response, and tumorigenesis. Xeroderma pigmentosum group A (XPA) is a core nucleotide excision repair (NER) factor essential for NER process. Here we show that SIRT1 plays an important role in the regulation of NER pathway. Downregulation of SIRT1 significantly sensitizes cells to UV irradiation. SIRT1 interacts with XPA, and the interaction is enhanced after UV irradiation. XPA can be acetylated at lysines 63 and 67. SIRT1 deacetylates XPA both in vitro and in cells. Importantly, SIRT1-mediated deacetylation of XPA is required for optimal NER pathway since XPA-deficient cells complemented with XPA-K6367Q, which mimics hyperacetylated XPA, display significantly higher UV sensitivity compared with the XPA cells complemented with wild-type XPA. Furthermore, SIRT1-mediated XPA deacetylation enhances its interaction with RPA32. Our results demonstrate that SIRT1 regulates NER pathway through modulation of XPA acetylation status.
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