The RAD9–RAD1–HUS1 (9.1.1) complex interacts with WRN and is crucial to regulate its response to replication fork stalling

The E3 ubiquitin ligase Rad18 guides DNA Polymerase eta (Polη) to sites of replication fork stalling and mono-ubiquitinates proliferating cell nuclear antigen (PCNA) to facilitate binding of Y family trans-lesion synthesis (TLS) DNA polymerases during TLS. However, it is unclear exactly how Rad18 is regulated in response to DNA damage and how Rad18 activity is coordinated with progression through different phases of the cell cycle. Here we identify Rad18 as a novel substrate of the essential protein kinase Cdc7 (also termed Dbf4/Drf1-dependent Cdc7 kinase [DDK]). A serine cluster in the Polη-binding motif of Rad18 is phosphorylated by DDK. Efficient association of Rad18 with Polη is dependent on DDK and is necessary for redistribution of Polη to sites of replication fork stalling. This is the first demonstration of Rad18 regulation by direct phosphorylation and provides a novel mechanism for integration of S phase progression with postreplication DNA repair to maintain genome stability.

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Oligodeoxynucleotide Binding to (CTG) · (CAG) Microsatellite Repeats Inhibits Replication Fork Stalling, Hairpin Formation, and Genome Instability

Molecular and Cellular Biology ◽

10.1128/mcb.01265-12 ◽

2012 ◽

Vol 33 (3) ◽

pp. 571-581 ◽

Cited By ~ 13

Author(s):

Guoqi Liu ◽

Xiaomi Chen ◽

Michael Leffak

Keyword(s):

Replication Fork ◽

Trinucleotide Repeat ◽

Cell Model ◽

Replication Stress ◽

Dna Hairpin ◽

Replication Fork Stalling ◽

Fork Stalling ◽

Hairpin Formation ◽

Lagging Strand

ABSTRACT(CTG)n· (CAG)ntrinucleotide repeat (TNR) expansion in the 3′ untranslated region of the dystrophia myotonica protein kinase (DMPK) gene causes myotonic dystrophy type 1. However, a direct link between TNR instability, the formation of noncanonical (CTG)n· (CAG)nstructures, and replication stress has not been demonstrated. In a human cell model, we found that (CTG)45· (CAG)45causes local replication fork stalling, DNA hairpin formation, and TNR instability. Oligodeoxynucleotides (ODNs) complementary to the (CTG)45· (CAG)45lagging-strand template eliminated DNA hairpin formation on leading- and lagging-strand templates and relieved fork stalling. Prolonged cell culture, emetine inhibition of lagging-strand synthesis, or slowing of DNA synthesis by low-dose aphidicolin induced (CTG)45· (CAG)45expansions and contractions. ODNs targeting the lagging-strand template blocked the time-dependent or emetine-induced instability but did not eliminate aphidicolin-induced instability. These results show directly that TNR replication stalling, replication stress, hairpin formation, and instability are mechanistically linkedin vivo.

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Replication-Fork Stalling and Processing at a Single Psoralen Interstrand Crosslink in Xenopus Egg Extracts

PLoS ONE ◽

10.1371/journal.pone.0018554 ◽

2011 ◽

Vol 6 (4) ◽

pp. e18554 ◽

Cited By ~ 14

Author(s):

Cyrille Le Breton ◽

Magali Hennion ◽

Paola B. Arimondo ◽

Olivier Hyrien

Keyword(s):

Replication Fork ◽

Interstrand Crosslink ◽

Egg Extracts ◽

Xenopus Egg ◽

Replication Fork Stalling ◽

Fork Stalling ◽

Xenopus Egg Extracts

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Histone acetyltransferase 1 is required for DNA replication fork function and stability

Journal of Biological Chemistry ◽

10.1074/jbc.ra120.013496 ◽

2020 ◽

Vol 295 (25) ◽

pp. 8363-8373 ◽

Cited By ~ 2

Author(s):

Paula A. Agudelo Garcia ◽

Callie M. Lovejoy ◽

Prabakaran Nagarajan ◽

Dongju Park ◽

Liudmila V. Popova ◽

...

Keyword(s):

Dna Replication ◽

Replication Fork ◽

Histone Acetyltransferase ◽

Dynamic Environment ◽

Chromatin Assembly ◽

Proximity Ligation Assay ◽

Histone H4 ◽

Replication Fork Progression ◽

Replication Fork Stalling ◽

Fork Stalling

The replisome is a protein complex on the DNA replication fork and functions in a dynamic environment at the intersection of parental and nascent chromatin. Parental nucleosomes are disrupted in front of the replication fork. The daughter DNA duplexes are packaged with an equal amount of parental and newly synthesized histones in the wake of the replication fork through the activity of the replication-coupled chromatin assembly pathway. Histone acetyltransferase 1 (HAT1) is responsible for the cytosolic diacetylation of newly synthesized histone H4 on lysines 5 and 12, which accompanies replication-coupled chromatin assembly. Here, using proximity ligation assay-based chromatin assembly assays and DNA fiber analysis, we analyzed the role of murine HAT1 in replication-coupled chromatin assembly. We demonstrate that HAT1 physically associates with chromatin near DNA replication sites. We found that the association of HAT1 with newly replicated DNA is transient, but can be stabilized by replication fork stalling. The association of HAT1 with nascent chromatin may be functionally relevant, as HAT1 loss decreased replication fork progression and increased replication fork stalling. Moreover, in the absence of HAT1, stalled replication forks were unstable, and newly synthesized DNA became susceptible to MRE11-dependent degradation. These results suggest that HAT1 links replication fork function to the proper processing and assembly of newly synthesized histones.

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