SPINDOC binds PARP1 to facilitate PARylation

AbstractSPINDOC is tightly associated with the histone H3K4me3 effector protein SPIN1. To gain a better understanding of the biological roles of SPINDOC, we identified its interacting proteins. Unexpectedly, SPINDOC forms two mutually exclusive protein complexes, one with SPIN1 and the other with PARP1. Consistent with its ability to directly interact with PARP1, SPINDOC expression is induced by DNA damage, likely by KLF4, and recruited to DNA lesions with dynamics that follows PARP1. In SPINDOC knockout cells, the levels of PARylation are reduced, in both the absence and presence of DNA damage. The SPINDOC/PARP1 interaction promotes the clearance of PARP1 from damaged DNA, and also impacts the expression of known transcriptional targets of PARP1. To address the in vivo roles of SPINDOC in PARP1 regulation, we generate SPINDOC knockout mice, which are viable, but slightly smaller than their wildtype counterparts. The KO mice display reduced levels of PARylation and, like PARP1 KO mice, are hypersensitive to IR-induced DNA damage. The findings identify a SPIN1-independent role for SPINDOC in the regulation of PARP1-mediated PARylation and the DNA damage response.

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Faculty Opinions recommendation of Activation of the cellular DNA damage response in the absence of DNA lesions.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1108695.571444 ◽

2008 ◽

Author(s):

Yosef Gruenbaum

Keyword(s):

Dna Damage ◽

Dna Damage Response ◽

Dna Lesions ◽

Damage Response ◽

Cellular Dna

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The DNA damage inducible lncRNA SCAT7 regulates genomic integrity and topoisomerase 1 turnover in lung adenocarcinoma

NAR Cancer ◽

10.1093/narcan/zcab002 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Luisa Statello ◽

Mohamad M Ali ◽

Silke Reischl ◽

Sagar Mahale ◽

Subazini Thankaswamy Kosalai ◽

...

Keyword(s):

Dna Damage ◽

Dna Damage Response ◽

Cancer Biology ◽

Topoisomerase I ◽

Cell Cycle Checkpoints ◽

Topoisomerase 1 ◽

Damage Response ◽

Promote Cell Survival

Abstract Despite the rapid improvements in unveiling the importance of lncRNAs in all aspects of cancer biology, there is still a void in mechanistic understanding of their role in the DNA damage response. Here we explored the potential role of the oncogenic lncRNA SCAT7 (ELF3-AS1) in the maintenance of genome integrity. We show that SCAT7 is upregulated in response to DNA-damaging drugs like cisplatin and camptothecin, where SCAT7 expression is required to promote cell survival. SCAT7 silencing leads to decreased proliferation of cisplatin-resistant cells in vitro and in vivo through interfering with cell cycle checkpoints and DNA repair molecular pathways. SCAT7 regulates ATR signaling, promoting homologous recombination. Importantly, SCAT7 also takes part in proteasome-mediated topoisomerase I (TOP1) degradation, and its depletion causes an accumulation of TOP1–cc structures responsible for the high levels of intrinsic DNA damage. Thus, our data demonstrate that SCAT7 is an important constituent of the DNA damage response pathway and serves as a potential therapeutic target for hard-to-treat drug resistant cancers.

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PAICS contributes to gastric carcinogenesis and participates in DNA damage response by interacting with histone deacetylase 1/2

Cell Death and Disease ◽

10.1038/s41419-020-2708-5 ◽

2020 ◽

Vol 11 (7) ◽

Author(s):

Nan Huang ◽

Chang Xu ◽

Liang Deng ◽

Xue Li ◽

Zhixuan Bian ◽

...

Keyword(s):

Dna Damage ◽

Histone Deacetylase ◽

Dna Damage Response ◽

De Novo ◽

Dna Damage Repair ◽

Histone Deacetylase 1 ◽

Damage Repair ◽

Damage Response

AbstractPhosphoribosylaminoimidazole carboxylase, phosphoribosylaminoimidazole succinocarboxamide synthetase (PAICS), an essential enzyme involved in de novo purine biosynthesis, is connected with formation of various tumors. However, the specific biological roles and related mechanisms of PAICS in gastric cancer (GC) remain unclear. In the present study, we identified for the first time that PAICS was significantly upregulated in GC and high expression of PAICS was correlated with poor prognosis of patients with GC. In addition, knockdown of PAICS significantly induced cell apoptosis, and inhibited GC cell growth both in vitro and in vivo. Mechanistic studies first found that PAICS was engaged in DNA damage response, and knockdown of PAICS in GC cell lines induced DNA damage and impaired DNA damage repair efficiency. Further explorations revealed that PAICS interacted with histone deacetylase HDAC1 and HDAC2, and PAICS deficiency decreased the expression of DAD51 and inhibited its recruitment to DNA damage sites by impairing HDAC1/2 deacetylase activity, eventually preventing DNA damage repair. Consistently, PAICS deficiency enhanced the sensitivity of GC cells to DNA damage agent, cisplatin (CDDP), both in vitro and in vivo. Altogether, our findings demonstrate that PAICS plays an oncogenic role in GC, which act as a novel diagnosis and prognostic biomarker for patients with GC.

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Slx4 Regulates DNA Damage Checkpoint-dependent Phosphorylation of the BRCT Domain Protein Rtt107/Esc4

Molecular Biology of the Cell ◽

10.1091/mbc.e05-08-0785 ◽

2006 ◽

Vol 17 (1) ◽

pp. 539-548 ◽

Cited By ~ 59

Author(s):

Tania M. Roberts ◽

Michael S. Kobor ◽

Suzanne A. Bastin-Shanower ◽

Miki Ii ◽

Sonja A. Horte ◽

...

Keyword(s):

Dna Damage ◽

Dna Damage Response ◽

Dna Damage Checkpoint ◽

Checkpoint Activation ◽

Alkylation Damage ◽

Binding Partner ◽

Replication Restart ◽

Damage Response ◽

Domain Protein

RTT107 (ESC4, YHR154W) encodes a BRCA1 C-terminal-domain protein that is important for recovery from DNA damage during S phase. Rtt107 is a substrate of the checkpoint protein kinase Mec1, although the mechanism by which Rtt107 is targeted by Mec1 after checkpoint activation is currently unclear. Slx4, a component of the Slx1-Slx4 structure-specific nuclease, formed a complex with Rtt107. Deletion of SLX4 conferred many of the same DNA-repair defects observed in rtt107Δ, including DNA damage sensitivity, prolonged DNA damage checkpoint activation, and increased spontaneous DNA damage. These phenotypes were not shared by the Slx4 binding partner Slx1, suggesting that the functions of the Slx4 and Slx1 proteins in the DNA damage response were not identical. Of particular interest, Slx4, but not Slx1, was required for phosphorylation of Rtt107 by Mec1 in vivo, indicating that Slx4 was a mediator of DNA damage-dependent phosphorylation of the checkpoint effector Rtt107. We propose that Slx4 has roles in the DNA damage response that are distinct from the function of Slx1-Slx4 in maintaining rDNA structure and that Slx4-dependent phosphorylation of Rtt107 by Mec1 is critical for replication restart after alkylation damage.

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Dephosphorylation of the C-terminal Tyrosyl Residue of the DNA Damage-related Histone H2A.X Is Mediated by the Protein Phosphatase Eyes Absent

Journal of Biological Chemistry ◽

10.1074/jbc.c900032200 ◽

2009 ◽

Vol 284 (24) ◽

pp. 16066-16070 ◽

Cited By ~ 88

Author(s):

Navasona Krishnan ◽

Dae Gwin Jeong ◽

Suk-Kyeong Jung ◽

Seong Eon Ryu ◽

Andrew Xiao ◽

...

Keyword(s):

Dna Damage ◽

Dna Damage Response ◽

Mammalian Cells ◽

Protein Tyrosine Phosphatases ◽

Histone H2a ◽

Eyes Absent ◽

Damage Repair ◽

Damage Response

In mammalian cells, the DNA damage-related histone H2A variant H2A.X is characterized by a C-terminal tyrosyl residue, Tyr-142, which is phosphorylated by an atypical kinase, WSTF. The phosphorylation status of Tyr-142 in H2A.X has been shown to be an important regulator of the DNA damage response by controlling the formation of γH2A.X foci, which are platforms for recruiting molecules involved in DNA damage repair and signaling. In this work, we present evidence to support the identification of the Eyes Absent (EYA) phosphatases, protein-tyrosine phosphatases of the haloacid dehalogenase superfamily, as being responsible for dephosphorylating the C-terminal tyrosyl residue of histone H2A.X. We demonstrate that EYA2 and EYA3 displayed specificity for Tyr-142 of H2A.X in assays in vitro. Suppression of eya3 by RNA interference resulted in elevated basal phosphorylation and inhibited DNA damage-induced dephosphorylation of Tyr-142 of H2A.X in vivo. This study provides the first indication of a physiological substrate for the EYA phosphatases and suggests a novel role for these enzymes in regulation of the DNA damage response.

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DNA lesions and DNA damage response: Even long lasting relationships need a "break"

Cell Cycle ◽

10.4161/cc.7.23.7178 ◽

2008 ◽

Vol 7 (23) ◽

pp. 3653-3658 ◽

Cited By ~ 3

Author(s):

Evi Soutoglou

Keyword(s):

Dna Damage ◽

Dna Damage Response ◽

Dna Lesions ◽

Damage Response

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MORC2 regulates DNA damage response through a PARP1-dependent pathway

Nucleic Acids Research ◽

10.1093/nar/gkz545 ◽

2019 ◽

Vol 47 (16) ◽

pp. 8502-8520 ◽

Cited By ~ 4

Author(s):

Lin Zhang ◽

Da-Qiang Li

Keyword(s):

Dna Damage ◽

Zinc Finger ◽

Chromatin Remodeling ◽

Dna Damage Response ◽

Mammalian Cells ◽

Cellular Response ◽

Genotoxic Stress ◽

Underlying Mechanism ◽

Dna Lesions ◽

Damage Response

Abstract Microrchidia family CW-type zinc finger 2 (MORC2) is a newly identified chromatin remodeling enzyme with an emerging role in DNA damage response (DDR), but the underlying mechanism remains largely unknown. Here, we show that poly(ADP-ribose) polymerase 1 (PARP1), a key chromatin-associated enzyme responsible for the synthesis of poly(ADP-ribose) (PAR) polymers in mammalian cells, interacts with and PARylates MORC2 at two residues within its conserved CW-type zinc finger domain. Following DNA damage, PARP1 recruits MORC2 to DNA damage sites and catalyzes MORC2 PARylation, which stimulates its ATPase and chromatin remodeling activities. Mutation of PARylation residues in MORC2 results in reduced cell survival after DNA damage. MORC2, in turn, stabilizes PARP1 through enhancing acetyltransferase NAT10-mediated acetylation of PARP1 at lysine 949, which blocks its ubiquitination at the same residue and subsequent degradation by E3 ubiquitin ligase CHFR. Consequently, depletion of MORC2 or expression of an acetylation-defective PARP1 mutant impairs DNA damage-induced PAR production and PAR-dependent recruitment of DNA repair proteins to DNA lesions, leading to enhanced sensitivity to genotoxic stress. Collectively, these findings uncover a previously unrecognized mechanistic link between MORC2 and PARP1 in the regulation of cellular response to DNA damage.

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Recent advances in the nucleolar responses to DNA double-strand breaks

Nucleic Acids Research ◽

10.1093/nar/gkaa713 ◽

2020 ◽

Vol 48 (17) ◽

pp. 9449-9461

Author(s):

Lea Milling Korsholm ◽

Zita Gál ◽

Blanca Nieto ◽

Oliver Quevedo ◽

Stavroula Boukoura ◽

...

Keyword(s):

Dna Damage ◽

Dna Repair ◽

Dna Damage Response ◽

Ribosomal Dna ◽

Repetitive Sequences ◽

Dna Lesions ◽

Double Strand Breaks ◽

Dna Double Strand Breaks ◽

Strand Breaks ◽

Damage Response

Abstract DNA damage poses a serious threat to human health and cells therefore continuously monitor and repair DNA lesions across the genome. Ribosomal DNA is a genomic domain that represents a particular challenge due to repetitive sequences, high transcriptional activity and its localization in the nucleolus, where the accessibility of DNA repair factors is limited. Recent discoveries have significantly extended our understanding of how cells respond to DNA double-strand breaks (DSBs) in the nucleolus, and new kinases and multiple down-stream targets have been identified. Restructuring of the nucleolus can occur as a consequence of DSBs and new data point to an active regulation of this process, challenging previous views. Furthermore, new insights into coordination of cell cycle phases and ribosomal DNA repair argue against existing concepts. In addition, the importance of nucleolar-DNA damage response (n-DDR) mechanisms for maintenance of genome stability and the potential of such factors as anti-cancer targets is becoming apparent. This review will provide a detailed discussion of recent findings and their implications for our understanding of the n-DDR. The n-DDR shares features with the DNA damage response (DDR) elsewhere in the genome but is also emerging as an independent response unique to ribosomal DNA and the nucleolus.

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