Single-Strand Break End Resection in Genome Integrity: Mechanism and Regulation by APE2

International Journal of Molecular Sciences, Journal Year: 2018, Volume and Issue: 19(8), P. 2389 - 2389

Published: Aug. 14, 2018

DNA single-strand breaks (SSBs) occur more than 10,000 times per mammalian cell each day, representing the most common type of damage. Unrepaired SSBs compromise replication and transcription programs, leading to genome instability. are associated with diseases such as cancer neurodegenerative disorders. Although canonical SSB repair pathway is activated SSBs, it remains unclear whether how unrepaired sensed signaled. In this review, we propose a new concept end resection for integrity. We four-step mechanism resection: sensing processing, well initiation, continuation, termination resection. also compare different mechanisms DSB in damage response (DDR) pathways. further discuss contributes signaling repair. focus on regulation by APE2 Finally, identify areas future study that may help us gain mechanistic insight into process Overall, review provides first comprehensive perspective

Language: Английский

---

APE1 senses DNA single-strand breaks for repair and signaling

Nucleic Acids Research, Journal Year: 2019, Volume and Issue: 48(4), P. 1925 - 1940

Published: Dec. 5, 2019

Abstract DNA single-strand breaks (SSBs) represent the most abundant type of damage. Unrepaired SSBs impair replication and transcription, leading to cancer neurodegenerative disorders. Although PARP1 XRCC1 are implicated in SSB repair pathway, it remains unclear how signaling pathways coordinated regulated. Using Xenopus egg extract vitro reconstitution systems, here we show that first sensed by APE1 initiate 3′–5′ end resection, followed APE2 recruitment continue resection. Notably, APE1’s exonuclease activity is critical for pathways. An exonuclease-deficient mutant identified somatic tissue from a patient highlighted significance etiology. In addition, interacts with PCNA, although PCNA dispensable activity. Taken together, propose two-step APE1/APE2-mediated mechanism resection couples damage response eukaryotic system.

Language: Английский

---

APE2 promotes DNA damage response pathway from a single-strand break

Nucleic Acids Research, Journal Year: 2018, Volume and Issue: 46(5), P. 2479 - 2494

Published: Jan. 9, 2018

As the most common type of DNA damage, single-strand breaks (SSBs) are primarily repaired by SSB repair mechanism. If not properly or promptly, unrepaired SSBs lead to genome stability and have been implicated in cancer neurodegenerative diseases. However, it remains unknown how recognized damage response (DDR) pathway, largely because lack a feasible experimental system. Here, we demonstrate evidence showing that an ATR-dependent checkpoint signaling is activated defined plasmid-based site-specific structure Xenopus HSS (high-speed supernatant) Notably, distinct requires APE2 canonical proteins, including ATR, ATRIP, TopBP1, Rad9 Claspin. Importantly, SSB-induced ATR DDR essential for repair. We others show interacts with PCNA via its PIP box preferentially ssDNA C-terminus Zf-GRF domain, conserved motif found >100 proteins involved DNA/RNA metabolism. identify novel mode APE2-PCNA interaction C-terminus. Mechanistically, Zf-GRF-PCNA facilitates 3'-5' end resection, protein complex assembly, pathway. Together, propose promotes ATR-Chk1 pathway from break.

Language: Английский

---

APE1 recruits ATRIP to ssDNA in an RPA-dependent and -independent manner to promote the ATR DNA damage response

eLife, Journal Year: 2023, Volume and Issue: 12

Published: May 22, 2023

Cells have evolved the DNA damage response (DDR) pathways in to replication stress or damage. In ATR-Chk1 DDR pathway, it has been proposed that ATR is recruited RPA-coated single-stranded (ssDNA) by direct ATRIP-RPA interaction. However, remains elusive how ATRIP ssDNA an RPA-independent manner. Here, we provide evidence APE1 directly associates recruit onto fashion. The N-terminal motif within required and sufficient for APE1-ATRIP interaction vitro distinct recruitment pathway activation Xenopus egg extracts. addition, with RPA70 RPA32 via two motifs. Taken together, our suggests recruits RPA-dependent -independent manner pathway.

Language: Английский

---

Distinct regulation of ATM signaling by DNA single-strand breaks and APE1

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Aug. 7, 2024

Abstract In response to DNA double-strand breaks or oxidative stress, ATM-dependent damage (DDR) is activated maintain genome integrity. However, it remains elusive whether and how single-strand (SSBs) activate ATM. Here, we provide direct evidence in Xenopus egg extracts that ATM-mediated DDR by a defined SSB structure. Our mechanistic studies reveal APE1 promotes the SSB-induced ATM through exonuclease activity recruitment sites. protein can form oligomers absence of directly stimulate kinase vitro. findings distinct mechanisms activation SSBs eukaryotic systems identify as activator kinase.

Language: Английский

---

Xenopus egg extract: A powerful tool to study genome maintenance mechanisms

Developmental Biology, Journal Year: 2017, Volume and Issue: 428(2), P. 300 - 309

Published: April 17, 2017

Language: Английский

---

TALENs and CRISPR/Cas9 fuel genetically engineered clinically relevant Xenopus tropicalis tumor models

genesis, Journal Year: 2017, Volume and Issue: 55(1-2)

Published: Jan. 1, 2017

Abstract The targeted nuclease revolution (TALENs, CRISPR/Cas9) now allows Xenopus researchers to rapidly generate custom on‐demand genetic knockout models. These novel methods perform reverse genetics are unprecedented and fueling a wide array of human disease models within the aquatic diploid model organism tropicalis (X. tropicalis) . This emerging technology review focuses on tools genetically engineered X. (GEXM), with focus establishment genuine clinically relevant cancer We believe that due particular advantageous characteristics, outlined this review, GEXM will become valuable alternative animal for modeling cancer. Furthermore, we provide perspectives how be used as platform elucidation therapeutic targets preclinical drug validation. Finally, also discuss some future prospects recent expansions adaptations CRISPR/Cas9 toolbox might influence push forward research.

Language: Английский

---

Integrative biology of native cell extracts: a new era for structural characterization of life processes

Biological Chemistry, Journal Year: 2019, Volume and Issue: 400(7), P. 831 - 846

Published: May 15, 2019

Advances in electron microscopy have provided unprecedented access to the structural characterization of large, flexible and heterogeneous complexes. Until recently, cryo-electron (cryo-EM) has been applied understand molecular organization either highly purified, isolated biomolecules or situ. An emerging field is developing, bridging gap between two approaches, focuses on studying native cell extracts. This demonstrated its potential by resolving structure fungal fatty acid synthase (FAS) at 4.7 Å [Fourier shell correlation (FSC) = 0.143]; FAS was not only less than 50% enriched, but also retained higher-order binders, previously unknown. Although controversial sense that lysis step might introduce artifacts, extracts preserve aspects cellular function. In addition, are accessible, besides cryo-EM, modern proteomic methods, chemical cross-linking, network biology biophysical modeling. We expect automation imaging extracts, along with integration molecular/cell will provide remarkable achievements study closer-to-life biomolecular states pronounced biotechnological medical importance. Such steps will, eventually, bring us a closer description processes an integrative, holistic approach.

Language: Английский

---

A non-canonical role for the DNA glycosylase NEIL3 in suppressing APE1 endonuclease-mediated ssDNA damage

Journal of Biological Chemistry, Journal Year: 2020, Volume and Issue: 295(41), P. 14222 - 14235

Published: Aug. 14, 2020

The DNA glycosylase NEIL3 has been implicated in repair pathways including the base excision and interstrand cross-link via its and/or AP lyase activity, which are considered canonical roles of genome integrity. Compared with other glycosylases NEIL1 NEIL2, Xenopus laevis C terminus two highly conserved zinc finger motifs containing GRXF residues (designated as Zf-GRF). It demonstrated that minor endonuclease APE2 contains only one Zf-GRF motif mediating interaction single-strand (ssDNA), whereas major APE1 does not. appears repeat) dispensable for activity; however, potential function repeat integrity remains unknown. Here, we demonstrate evidence was associated a higher affinity shorter ssDNA than single motif. Notably, our protein-protein assays show but not interacted APE2. We further reveal activity on dsDNA is compromised by repeat, within sufficient to prevent such APE1. In addition, COMET excess reduces damage oxidative stress egg extracts. Together, results suggest noncanonical role distinct suppressing endonuclease-mediated breakage.

Language: Английский

---

Function and molecular mechanisms of APE2 in genome and epigenome integrity

Mutation Research/Reviews in Mutation Research, Journal Year: 2020, Volume and Issue: 787, P. 108347 - 108347

Published: Nov. 16, 2020

Language: Английский

---