Central Role for the Werner Syndrome Protein/Poly(ADP-Ribose) Polymerase 1 Complex in the Poly(ADP-Ribosyl)ation Pathway after DNA Damage

ABSTRACT A defect in the Werner syndrome protein (WRN) leads to the premature aging disease Werner syndrome (WS). Hallmark features of cells derived from WS patients include genomic instability and hypersensitivity to certain DNA-damaging agents. WRN contains a highly conserved region, the RecQ conserved domain, that plays a central role in protein interactions. We searched for proteins that bound to this region, and the most prominent direct interaction was with poly(ADP-ribose) polymerase 1 (PARP-1), a nuclear enzyme that protects the genome by responding to DNA damage and facilitating DNA repair. In pursuit of a functional interaction between WRN and PARP-1, we found that WS cells are deficient in the poly(ADP-ribosyl)ation pathway after they are treated with the DNA-damaging agents H2O2 and methyl methanesulfonate. After cellular stress, PARP-1 itself becomes activated, but the poly(ADP-ribosyl)ation of other cellular proteins is severely impaired in WS cells. Overexpression of the PARP-1 binding domain of WRN strongly inhibits the poly(ADP-ribosyl)ation activity in H2O2-treated control cell lines. These results indicate that the WRN/PARP-1 complex plays a key role in the cellular response to oxidative stress and alkylating agents, suggesting a role for these proteins in the base excision DNA repair pathway.

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The Caenorhabditis elegans Werner syndrome protein participates in DNA damage checkpoint and DNA repair in response to CPT-induced double-strand breaks

Cellular Signalling ◽

10.1016/j.cellsig.2015.12.006 ◽

2016 ◽

Vol 28 (3) ◽

pp. 214-223 ◽

Cited By ~ 6

Author(s):

Moonjung Hyun ◽

Seoyun Choi ◽

Tinna Stevnsner ◽

Byungchan Ahn

Keyword(s):

Dna Damage ◽

Dna Repair ◽

Caenorhabditis Elegans ◽

Werner Syndrome ◽

Double Strand Breaks ◽

Dna Damage Checkpoint ◽

Strand Breaks ◽

Werner Syndrome Protein ◽

Syndrome Protein

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PARP inhibitors for cancer therapy

Expert Reviews in Molecular Medicine ◽

10.1017/s146239940500904x ◽

2005 ◽

Vol 7 (4) ◽

pp. 1-20 ◽

Cited By ~ 129

Author(s):

Nicola J. Curtin

Keyword(s):

Dna Damage ◽

Dna Repair ◽

Topoisomerase I ◽

Alkylating Agents ◽

Parp Inhibitors ◽

Ionising Radiation ◽

Parp Inhibition ◽

Tumour Regression ◽

Dna Breaks ◽

Parp 1

Poly(ADP-ribose) polymerase 1 (PARP-1) is a zinc-finger DNA-binding enzyme that is activated by binding to DNA breaks. Poly(ADP-ribosyl)ation of nuclear proteins by PARP-1 converts DNA damage into intracellular signals that activate either DNA repair by the base-excision pathway or cell death. A family of 18 PARPs has been identified, but only the most abundant, PARP-1 and PARP-2, which are both nuclear enzymes, are activated by DNA damage. PARP inhibitors of ever-increasing potency have been developed in the 40 years since the discovery of PARP-1, both as tools for the investigation of PARP-1 function and as potential modulators of DNA-repair-mediated resistance to cytotoxic therapy. Owing to the high level of homology between the catalytic domains of PARP-1 and PARP-2, the inhibitors probably affect both enzymes. Convincing biochemical evidence, which has been corroborated by genetic manipulation of PARP-1 activity, shows that PARP inhibition is associated with increased sensitivity to DNA-alkylating agents, topoisomerase I poisons and ionising radiation. Novel PARP inhibitors of sufficient potency and suitable pharmacokinetic properties to allow evaluation in animal models have been shown to enhance the antitumour activity of temozolomide (a DNA-methylating agent), topoisomerase poisons and ionising radiation; indeed, the combination with temozolomide resulted in complete tumour regression in two independent studies. The combination of a PARP inhibitor and temozolomide is currently undergoing clinical evaluation for the first time.

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The Werner syndrome protein at the crossroads of DNA repair and apoptosis

Mechanisms of Ageing and Development ◽

10.1016/j.mad.2004.06.004 ◽

2004 ◽

Vol 125 (8) ◽

pp. 521-528 ◽

Cited By ~ 26

Author(s):

Lucio Comai ◽

Baomin Li

Keyword(s):

Dna Repair ◽

Werner Syndrome ◽

Werner Syndrome Protein ◽

Syndrome Protein

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The Werner syndrome protein is required for recruitment of chromatin assembly factor 1 following DNA damage

Oncogene ◽

10.1038/sj.onc.1210150 ◽

2006 ◽

Vol 26 (26) ◽

pp. 3811-3822 ◽

Cited By ~ 13

Author(s):

R Jiao ◽

J A Harrigan ◽

I Shevelev ◽

T Dietschy ◽

N Selak ◽

...

Keyword(s):

Dna Damage ◽

Werner Syndrome ◽

Chromatin Assembly ◽

Chromatin Assembly Factor ◽

Assembly Factor ◽

Werner Syndrome Protein ◽

Syndrome Protein

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Werner Syndrome Protein Phosphorylation by Abl Tyrosine Kinase Regulates Its Activity and Distribution

Molecular and Cellular Biology ◽

10.1128/mcb.23.18.6385-6395.2003 ◽

2003 ◽

Vol 23 (18) ◽

pp. 6385-6395 ◽

Cited By ~ 48

Author(s):

Wen-Hsing Cheng ◽

Cayetano von Kobbe ◽

Patricia L. Opresko ◽

Kesha M. Fields ◽

Jian Ren ◽

...

Keyword(s):

Dna Damage ◽

Kinase Inhibitor ◽

Werner Syndrome ◽

Sti 571 ◽

Abl Kinase ◽

Werner Syndrome Protein ◽

Domain 3 ◽

Syndrome Protein

ABSTRACT The Werner syndrome protein (WRN) is a caretaker of the human genome, and the Abl kinase is a regulator of the DNA damage response. Aberrant DNA repair has been linked to the development of cancer. Here, we have identified a direct binding between WRN and c-Abl in vitro via the N-terminal and central regions of WRN and the Src homology domain 3 of c-Abl. After bleomycin treatment in culture, WRN and c-Abl are dissociated and followed by an Abl kinase-dependent WRN relocalization to the nucleoplasm. WRN is a substrate of c-Abl in vitro and in vivo. WRN is tyrosine phosphorylated either transiently by treatment of HeLa cells with bleomycin or constitutively in cells from chronic myeloid leukemia (CML) patients, and these phosphorylations are prevented by treatment with the Abl kinase inhibitor STI-571. Tyrosine phosphorylation of WRN results in inhibition of both WRN exonuclease and helicase activities. Furthermore, anti-WRN immunoprecipitates from CML cells treated with STI-571 show increased 3′→5′ exonuclease activity. These findings suggest a novel signaling pathway by which c-Abl mediates WRN nuclear localization and catalytic activities in response to DNA damage.

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