53BP1 promotes non-homologous end joining of telomeres by increasing chromatin mobility

Dimitrova, Nadya; Chen, Yi-Chun M.; Spector, David L.; Lange, Titia de

doi:10.1038/nature07433

Cited by 513 publications

(595 citation statements)

References 32 publications

Supporting

Mentioning

554

Contrasting

Unclassified

Order By: Relevance

“…This observation is consistent with previous linkage between 53BP1 and NHEJ that 53BP1 mainly functions in NHEJ repair pathway. 55,56 How BZLF1 disrupts NHEJ is not clear at this stage. BZLF1 has been reported to bind to Ku80 through its C-terminal region.…”

Section: Discussionmentioning

confidence: 99%

Epstein–Barr virus BZLF1 protein impairs accumulation of host DNA damage proteins at damage sites in response to DNA damage

Yang

Deng

Hau

et al. 2015

Laboratory Investigation

View full text Add to dashboard Cite

Epstein-Barr virus (EBV) infection is closely associated with several human malignancies including nasopharyngeal carcinoma (NPC). The EBV immediate-early protein BZLF1 is the key mediator that switches EBV infection from latent to lytic forms. The lytic form of EBV infection has been implicated in human carcinogenesis but its molecular mechanisms remain unclear. BZLF1 has been shown to be a binding partner of several DNA damage response (DDR) proteins. Its functions in host DDR remain unknown. Thus, we explore the effects of BZLF1 on cellular response to DNA damage in NPC cells. We found that expression of BZLF1 impaired the binding between RNF8 and MDC1 (mediator of DNA damage checkpoint 1), which in turn interfered with the localization of RNF8 and 53BP1 to the DNA damage sites. The RNF8-53BP1 pathway is important for repair of DNA double-strand breaks and DNA damage-induced G2/M checkpoint activation. Our results showed that, by impairing DNA damage repair as well as abrogating G2/M checkpoint, BZLF1 induced genomic instability and rendered cells more sensitive to ionizing radiation. Moreover, the blockage of 53BP1 and RNF8 foci formation was recapitulated in EBV-infected cells. Taken together, our study raises the possibility that, by causing mis-localization of important DDR proteins, BZLF1 may function as a link between lytic EBV infection and impaired DNA damage repair, thus contributing to the carcinogenesis of EBV-associated human epithelial malignancies. Epstein-Barr virus (EBV) is a gamma herpesvirus and infection with EBV is associated with a variety of epithelial and B-cell cancers. 1,2 EBV has a biphasic life cycle consisting of latent and lytic stages. The switch from latent to lytic infection is triggered by the EBV immediate-early transcription factor, BZLF1 (ZEBRA, Zta, Z, EB1). 3,4 A number of reports have demonstrated that lytic EBV activation is intimately linked to the pathogenesis of EBV-induced malignancies including the development of NPC. [5][6][7][8] The mammalian DNA damage response (DDR) network has pivotal roles in maintaining genome stability and tumor suppression. [9][10][11][12][13] In the presence of double-strand break (DSBs), the protein complex composed of MRE11-RAD50-NBS1 (MRN) recruits and activates the ataxia-telangiectasiamutated (ATM) kinase at the vicinity of DSBs, 10 which leads to the phosphorylation of the histone variant H2AX (γH2AX). γH2AX decorates chromatin domains flanking DSBs, and is directly engaged by the mediator of DNA damage checkpoint 1 (MDC1). MDC1 loading onto the damaged chromatin subsequently permits the productive accumulation of a cohort of DNA damage signaling and mediator proteins. 14,15 In particular, the RING finger ubiquitin ligase RNF8 is targeted to MDC1 via its phospho-binding forkheadassociated domain, where it initiates a cascade of chromatin ubiquitination events important for tethering of DNA damage mediator and repair proteins, including 53BP1 and BRCA1, [16][17][18][19] the dysregulation of which compromises genome stability and cont...

show abstract

Section: Discussionmentioning

confidence: 99%

Epstein–Barr virus BZLF1 protein impairs accumulation of host DNA damage proteins at damage sites in response to DNA damage

Yang

Deng

Hau

et al. 2015

Laboratory Investigation

View full text Add to dashboard Cite

show abstract

“…shRNA-mediated depletion of TRF2 resulted in uncapped telomeres that are repaired via the classic non-homologous end joining (C-NHEJ)-mediated DNA repair pathway, generating endto-end chromosomal fusions that require the activation of the ATM-CHK2 pathway [44,45]. In contrast, removal of mPOT1a/b from telomeres resulted in increased telomere sister chromatid exchanges (T-SCEs) due to elevated HDR at telomeres [13,16,46].…”

Section: Impaired Hdr Of Dysfunctional Telomeres In Mino80 ∆/∆ Mefsmentioning

confidence: 99%

The mINO80 chromatin remodeling complex is required for efficient telomere replication and maintenance of genome stability

et al. 2013

View full text Add to dashboard Cite

The INO80 (inositol requiring mutant 80) chromatin remodeling complex plays important roles in transcriptional regulation and DNA replication and repair, and consists of several functional protein subunits, including the critical Ino80 ATPase catalytic subunit. While the function of INO80 has been studied in yeast and mammalian cell lines, we do not know how mIno80 contributes to the maintenance of genome stability to prevent cancer development in mice. Here, we use a conditional knockout approach to explore the cellular and organismal functions of mIno80. Deletion of mIno80 results in profound cellular proliferative defects and activation of p21-dependent cellular senescence. While mIno80 is required for efficient repair of DNA double strand breaks, its depletion did not impact upon the formation of γ-H2AX and 53BP1 DNA damage foci, or the activation of the ATM-CHK2-dependent DNA damage response. mIno80 deletion inhibited the generation of single-strand DNA, resulting in defects in homology-directed DNA repair (HDR) at telomeres. Fragile telomeres were prominent in mIno80 ∆/∆ MEFs, suggesting that chromatin remodeling is required for efficient telomere replication. mIno80 −/− mouse embryos die early during embryogenesis, while conditional deletion of mIno80 in adult mice results in weight loss and premature death. In a p53 −/− tumorprone background, mIno80 haploinsufficiency favored the development of sarcomas. Our studies suggest that the mIno80 chromatin remodeling complex plays important roles in telomere replication, HDR-mediated repair of dysfunctional telomeres, and maintenance of genome stability.

show abstract

“…IF for γH2AX (Ab clone; Millipore, JBW301), 53BP1 (Abcam, ab175933), MDC1 (Ab clone; Millipore, P2B11), and RPA (Abcam, ab2175) was performed as described (Celli and de Lange 2005;Dimitrova et al 2008). For IF staining of myc-PHF11, FH2-PHF11 (HA IF), and RPA32-myc (Gong and de Lange 2010), the in situ cell fractionation protocol was used (Mirzoeva and Petrini 2001).…”

Section: If and If-fishmentioning

confidence: 99%

PHF11 promotes DSB resection, ATR signaling, and HR

et al. 2017

Self Cite

View full text Add to dashboard Cite

Resection of double-strand breaks (DSBs) plays a critical role in their detection and appropriate repair. The 3 ′ ssDNA protrusion formed through resection activates the ATR-dependent DNA damage response (DDR) and is required for DSB repair by homologous recombination (HR). Here we report that PHF11 (plant homeodomain finger 11) encodes a previously unknown DDR factor involved in 5 ′ end resection, ATR signaling, and HR. PHF11 was identified based on its association with deprotected telomeres and localized to sites of DNA damage in S phase. Depletion of PHF11 diminished the ATR signaling response to telomere dysfunction and genome-wide DNA damage, reduced end resection at sites of DNA damage, resulted in compromised HR and misrejoining of S-phase DSBs, and increased the sensitivity to DNA-damaging agents. PHF11 interacted with the ssDNA-binding protein RPA and was found in a complex with several nucleases, including the 5 ′ dsDNA exonuclease EXO1. Biochemical experiments demonstrated that PHF11 stimulates EXO1 by overcoming its inhibition by RPA, suggesting that PHF11 acts (in part) by promoting 5 ′ end resection at RPA-bound sites of DNA damage. These findings reveal a role for PHF11 in DSB resection, DNA damage signaling, and DSB repair.[Keywords: PHF11; EXO1; RPA; ATR; DSB; resection; homologous recombination] Supplemental material is available for this article.Received October 9, 2016; revised version accepted December 22, 2016.Nuclear double-strand breaks (DSBs) activate the ATM and ATR kinase-dependent DNA damage response (DDR) pathways (for review, see Ciccia and Elledge 2010). Whereas the ATM kinase responds to the presence of dsDNA ends, activation of the ATR kinase requires the presence of ssDNA that is bound by RPA. In addition, activation of the ATR kinase requires the loading of the 9-1-1 complex on the double-stranded-single-stranded junction formed after 5 ′ end resection. Resection of the 5 ′ end of DSBs is therefore a critical step in the activation of ATR signaling. DSB resection is also required for the initiation of several DNA repair pathways, including homologous recombination (HR) and single-strand annealing (SSA) (for review, see Symington and Gautier 2011). HR can restore the original DNA sequence using the sister chromatid as a template for repair. After 5 ′ end resection, HR is initiated by the BRCA2-mediated loading of the Rad51 recombinase onto the ssDNA. In the absence of HR, S-phase DSBs can become a substrate for more error-prone DSB repair, including SSA and classical or alternative nonhomologous end-joining (NHEJ). DSB resection is initiated through the agency of BRCA1, the MRE11/RAD50/NBS1 (MRN) complex, and CtIP (for review, see Cejka 2015). The outcome is a ssDNA end with a short (∼20-nucleotide [nt]) 3 ′ overhang that is a substrate for further nucleolytic attack by EXO1, a dsDNA exonuclease that degrades only the 5 ′ strand to leave a 3 ′ overhang that can be thousands of nucleotides in length. In addition, an overlapping pathway involving the DNA2 nuclease acting in conjun...

show abstract

53BP1 promotes non-homologous end joining of telomeres by increasing chromatin mobility

Cited by 513 publications

References 32 publications

Epstein–Barr virus BZLF1 protein impairs accumulation of host DNA damage proteins at damage sites in response to DNA damage

Epstein–Barr virus BZLF1 protein impairs accumulation of host DNA damage proteins at damage sites in response to DNA damage

The mINO80 chromatin remodeling complex is required for efficient telomere replication and maintenance of genome stability

PHF11 promotes DSB resection, ATR signaling, and HR

Contact Info

Product

Resources

About