Repair of gaps opposite lesions by homologous recombination in mammalian cells

Sheera Adar, Lior Izhar, Ayal Hendel, Nicholas Geacintov, Zvi Livneh

Research output: Contribution to journalArticle

Abstract

Damages in the DNA template inhibit the progression of replication, which may cause single-stranded gaps. Such situations can be tolerated by translesion DNA synthesis (TLS), or by homology-dependent repair (HDR), which is based on transfer or copying of the missing information from the replicated sister chromatid. Whereas it is well established that TLS plays an important role in DNA damage tolerance in mammalian cells, it is unknown whether HDR operates in this process. Using a newly developed plasmid-based assay that distinguishes between the three mechanisms of DNA damage tolerance, we found that mammalian cells can efficiently utilize HDR to repair DNA gaps opposite an abasic site or benzo[a]pyrene adduct. The majority of these events occurred by a physical strand transfer (homologous recombination repair; HRR), rather than a template switch mechanism. Furthermore, cells deficient in either the human RAD51 recombination protein or NBS1, but not Rad18, exhibited decreased gap repair through HDR, indicating a role for these proteins in DNA damage tolerance. To our knowledge, this is the first direct evidence of gap-lesion repair via HDR in mammalian cells, providing further molecular insight into the potential activity of HDR in overcoming replication obstacles and maintaining genome stability.

Original languageEnglish (US)
Article numbergkp632
Pages (from-to)5737-5748
Number of pages12
JournalNucleic Acids Research
Volume37
Issue number17
DOIs
StatePublished - Aug 4 2009

Fingerprint

Homologous Recombination
DNA Damage
Recombinational DNA Repair
Chromatids
Genomic Instability
Benzo(a)pyrene
DNA
DNA Repair
Genetic Recombination
Plasmids
Proteins

ASJC Scopus subject areas

  • Genetics

Cite this

Repair of gaps opposite lesions by homologous recombination in mammalian cells. / Adar, Sheera; Izhar, Lior; Hendel, Ayal; Geacintov, Nicholas; Livneh, Zvi.

In: Nucleic Acids Research, Vol. 37, No. 17, gkp632, 04.08.2009, p. 5737-5748.

Research output: Contribution to journalArticle

Adar, Sheera ; Izhar, Lior ; Hendel, Ayal ; Geacintov, Nicholas ; Livneh, Zvi. / Repair of gaps opposite lesions by homologous recombination in mammalian cells. In: Nucleic Acids Research. 2009 ; Vol. 37, No. 17. pp. 5737-5748.
@article{06331d06bf51488382f035003a3b837d,
title = "Repair of gaps opposite lesions by homologous recombination in mammalian cells",
abstract = "Damages in the DNA template inhibit the progression of replication, which may cause single-stranded gaps. Such situations can be tolerated by translesion DNA synthesis (TLS), or by homology-dependent repair (HDR), which is based on transfer or copying of the missing information from the replicated sister chromatid. Whereas it is well established that TLS plays an important role in DNA damage tolerance in mammalian cells, it is unknown whether HDR operates in this process. Using a newly developed plasmid-based assay that distinguishes between the three mechanisms of DNA damage tolerance, we found that mammalian cells can efficiently utilize HDR to repair DNA gaps opposite an abasic site or benzo[a]pyrene adduct. The majority of these events occurred by a physical strand transfer (homologous recombination repair; HRR), rather than a template switch mechanism. Furthermore, cells deficient in either the human RAD51 recombination protein or NBS1, but not Rad18, exhibited decreased gap repair through HDR, indicating a role for these proteins in DNA damage tolerance. To our knowledge, this is the first direct evidence of gap-lesion repair via HDR in mammalian cells, providing further molecular insight into the potential activity of HDR in overcoming replication obstacles and maintaining genome stability.",
author = "Sheera Adar and Lior Izhar and Ayal Hendel and Nicholas Geacintov and Zvi Livneh",
year = "2009",
month = "8",
day = "4",
doi = "10.1093/nar/gkp632",
language = "English (US)",
volume = "37",
pages = "5737--5748",
journal = "Nucleic Acids Research",
issn = "0305-1048",
publisher = "Oxford University Press",
number = "17",

}

TY - JOUR

T1 - Repair of gaps opposite lesions by homologous recombination in mammalian cells

AU - Adar, Sheera

AU - Izhar, Lior

AU - Hendel, Ayal

AU - Geacintov, Nicholas

AU - Livneh, Zvi

PY - 2009/8/4

Y1 - 2009/8/4

N2 - Damages in the DNA template inhibit the progression of replication, which may cause single-stranded gaps. Such situations can be tolerated by translesion DNA synthesis (TLS), or by homology-dependent repair (HDR), which is based on transfer or copying of the missing information from the replicated sister chromatid. Whereas it is well established that TLS plays an important role in DNA damage tolerance in mammalian cells, it is unknown whether HDR operates in this process. Using a newly developed plasmid-based assay that distinguishes between the three mechanisms of DNA damage tolerance, we found that mammalian cells can efficiently utilize HDR to repair DNA gaps opposite an abasic site or benzo[a]pyrene adduct. The majority of these events occurred by a physical strand transfer (homologous recombination repair; HRR), rather than a template switch mechanism. Furthermore, cells deficient in either the human RAD51 recombination protein or NBS1, but not Rad18, exhibited decreased gap repair through HDR, indicating a role for these proteins in DNA damage tolerance. To our knowledge, this is the first direct evidence of gap-lesion repair via HDR in mammalian cells, providing further molecular insight into the potential activity of HDR in overcoming replication obstacles and maintaining genome stability.

AB - Damages in the DNA template inhibit the progression of replication, which may cause single-stranded gaps. Such situations can be tolerated by translesion DNA synthesis (TLS), or by homology-dependent repair (HDR), which is based on transfer or copying of the missing information from the replicated sister chromatid. Whereas it is well established that TLS plays an important role in DNA damage tolerance in mammalian cells, it is unknown whether HDR operates in this process. Using a newly developed plasmid-based assay that distinguishes between the three mechanisms of DNA damage tolerance, we found that mammalian cells can efficiently utilize HDR to repair DNA gaps opposite an abasic site or benzo[a]pyrene adduct. The majority of these events occurred by a physical strand transfer (homologous recombination repair; HRR), rather than a template switch mechanism. Furthermore, cells deficient in either the human RAD51 recombination protein or NBS1, but not Rad18, exhibited decreased gap repair through HDR, indicating a role for these proteins in DNA damage tolerance. To our knowledge, this is the first direct evidence of gap-lesion repair via HDR in mammalian cells, providing further molecular insight into the potential activity of HDR in overcoming replication obstacles and maintaining genome stability.

UR - http://www.scopus.com/inward/record.url?scp=73049102332&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=73049102332&partnerID=8YFLogxK

U2 - 10.1093/nar/gkp632

DO - 10.1093/nar/gkp632

M3 - Article

C2 - 19654238

AN - SCOPUS:73049102332

VL - 37

SP - 5737

EP - 5748

JO - Nucleic Acids Research

JF - Nucleic Acids Research

SN - 0305-1048

IS - 17

M1 - gkp632

ER -