From structure to mechanism—understanding initiation of DNA replication

Riera, Alberto; Barbon, Marta; Noguchi, Yasunori; Reuter, L. Maximilian; Schneider, Sarah; Speck, Christian

doi:10.1101/gad.298232.117

Cited by 90 publications

(89 citation statements)

References 168 publications

(314 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Cdt1, Orc1)(RIERA 2017). Notably, within CA samples, we observed an increase in expression of genes associated with proliferative responses (Pcna, Cdh3) concordant with our histopathological analysis.…”

supporting

confidence: 88%

Transcriptional profiling of the murine airway response to acute ozone exposure

Tovar

Smith

Thomas

et al. 2019

Preprint

View full text Add to dashboard Cite

Exposure to ambient ozone (O3) pollution causes airway inflammation, epithelial injury, and decreased lung function. Long-term exposure is associated with increased mortality and exacerbations of respiratory conditions. While the adverse health effects of O3 exposure have been thoroughly described, less is known about the molecular processes that drive these outcomes. The aim of this study was to describe the cellular and molecular alterations observed in murine airways after exposure to either 1 or 2 ppm O3. After exposing adult, female C57BL/6J mice to filtered air, 1 or 2 ppm O3 for 3 hours, we assessed hallmark responses including airway inflammatory cell counts, epithelial permeability, cytokine secretion, and morphological alterations of the large airways. Further, we performed RNA-seq to profile gene expression in two critical tissues involved in O3 responses: conducting airways (CA) and airway macrophages (AM). We observed a concentration-dependent increase in airway inflammation and injury, and a large number of genes were differentially expressed in both target tissues at both concentrations of O3. Genes that were differentially expressed in CA were generally associated with barrier function, detoxification processes, and cellular proliferation. The differentially expressed genes in AM were associated with innate immune signaling, cytokine production, and extracellular matrix remodeling. Overall, our study has described transcriptional responses to acute O3 exposure, revealing both shared and unique gene expression patterns across multiple concentrations of O3 and in two important O3-responsive tissues. These profiles provide broad mechanistic insight into pulmonary O3 toxicity, and reveal a variety of targets for refined followup studies.

show abstract

supporting

confidence: 88%

Transcriptional profiling of the murine airway response to acute ozone exposure

Tovar

Smith

Thomas

et al. 2019

Preprint

View full text Add to dashboard Cite

show abstract

“…A subset of the many factors required to duplicate chromosomes assembles into a large and highly dynamic molecular machine called the replisome (Bell & Labib, ; Burgers & Kunkel, ; Kunkel & Burgers, ; Riera et al , ). Bacterial, viral and eukaryotic replisomes vary widely in their composition, but a common feature in all cases is that replisome assembly connects the DNA helicase that unwinds the parental DNA duplex to one or more of the DNA polymerases that synthesize the two daughter strands.…”

Section: Introductionmentioning

confidence: 99%

Histone H2A‐H2B binding by Pol α in the eukaryotic replisome contributes to the maintenance of repressive chromatin

et al. 2018

View full text Add to dashboard Cite

The eukaryotic replisome disassembles parental chromatin at DNA replication forks, but then plays a poorly understood role in the re‐deposition of the displaced histone complexes onto nascent DNA. Here, we show that yeast DNA polymerase α contains a histone‐binding motif that is conserved in human Pol α and is specific for histones H2A and H2B. Mutation of this motif in budding yeast cells does not affect DNA synthesis, but instead abrogates gene silencing at telomeres and mating‐type loci. Similar phenotypes are produced not only by mutations that displace Pol α from the replisome, but also by mutation of the previously identified histone‐binding motif in the CMG helicase subunit Mcm2, the human orthologue of which was shown to bind to histones H3 and H4. We show that chromatin‐derived histone complexes can be bound simultaneously by Mcm2, Pol α and the histone chaperone FACT that is also a replisome component. These findings indicate that replisome assembly unites multiple histone‐binding activities, which jointly process parental histones to help preserve silent chromatin during the process of chromosome duplication.

show abstract

“…CRL4 Cdt2 was first identified as an E3 ligase that targets Cdt1 for degradation. Cdt1 is an essential factor for DNA replication licensing that works together with ORC and Cdc6 to load MCM2‐7 helicase on replication origins (Maiorano, Moreau, & Mechali, ; Nishitani, Lygerou, Nishimoto, & Nurse, ; Riera et al., ). Once DNA replication is initiated, Cdt1 is inactivated by CRL4 Cdt2 to inhibit relicensing of replicated DNA (Abbas & Dutta, ; Arias & Walter, ).…”

Section: Introductionmentioning

confidence: 99%

Mutations at multiple CDK phosphorylation consensus sites on Cdt2 increase the affinity of CRL4^Cdt2 for PCNA and its ubiquitination activity in S phase

et al. 2018

View full text Add to dashboard Cite

CRL4 ubiquitin ligase plays an important role maintaining genome integrity during the cell cycle. A recent report suggested that Cdk1 negatively regulates CRL4 activity through phosphorylation of its receptor, Cdt2, but the involvement of phosphorylation remains unclear. To address this, we mutated all CDK consensus phosphorylation sites located in the C-terminal half region of Cdt2 (Cdt2-18A) and examined the effect on substrate degradation. We show that both cyclinA/Cdk2 and cyclinB/Cdk1 phosphorylated Cdt2 in vitro and that phosphorylation was reduced by the 18A mutation both in vitro and in vivo. The 18A mutation increased the affinity of Cdt2 to PCNA, and a high amount of Cdt2-18A was colocalized with PCNA foci during S phase in comparison with Cdt2-WT. Poly-ubiquitination activity to Cdt1 was concomitantly enhanced in cells expressing Cdt2-18A. Other CRL4 substrates, Set8 and thymine DNA glycosylase, begin to accumulate around late S phase to G2 phase, but the accumulation was prevented in Cdt2-18A cells. Furthermore, mitotic degradation of Cdt1 after UV irradiation was induced in these cells. Our results suggest that CDK-mediated phosphorylation of Cdt2 inactivates its ubiquitin ligase activity by reducing its affinity to PCNA, an important strategy for regulating the levels of key proteins in the cell cycle.

show abstract

From structure to mechanism—understanding initiation of DNA replication

Cited by 90 publications

References 168 publications

Transcriptional profiling of the murine airway response to acute ozone exposure

Transcriptional profiling of the murine airway response to acute ozone exposure

Histone H2A‐H2B binding by Pol α in the eukaryotic replisome contributes to the maintenance of repressive chromatin

Mutations at multiple CDK phosphorylation consensus sites on Cdt2 increase the affinity of CRL4^Cdt2 for PCNA and its ubiquitination activity in S phase

Contact Info

Product

Resources

About

From structure to mechanism—understanding initiation of DNA replication

Cited by 90 publications

References 168 publications

Transcriptional profiling of the murine airway response to acute ozone exposure

Transcriptional profiling of the murine airway response to acute ozone exposure

Histone H2A‐H2B binding by Pol α in the eukaryotic replisome contributes to the maintenance of repressive chromatin

Mutations at multiple CDK phosphorylation consensus sites on Cdt2 increase the affinity of CRL4Cdt2 for PCNA and its ubiquitination activity in S phase

Contact Info

Product

Resources

About

Mutations at multiple CDK phosphorylation consensus sites on Cdt2 increase the affinity of CRL4^Cdt2 for PCNA and its ubiquitination activity in S phase