The Replisome-Coupled E3 Ubiquitin Ligase Rtt101Mms22 Counteracts Mrc1 Function to Tolerate Genotoxic Stress

Autor: Brian Luke, Matthias Peter, Karim Labib, Wojciech Piwko, Marija Maric, Martina Dees, Caroline Wilson-Zbinden, Andre Melnik, Vanessa Kellner, Paola Picotti, René Schellhaas, Lisa Kastner, Raymond Buser
Jazyk: angličtina
Rok vydání: 2016
Předmět:
0301 basic medicine
Genetic Screens
Cancer Research
Gene Identification and Analysis
Synthesis Phase
Cell Cycle Proteins
Eukaryotic DNA replication
DNA-Directed DNA Polymerase
Pre-replication complex
Biochemistry
Substrate Specificity
Ligases
0302 clinical medicine
Cell Cycle and Cell Division
Homologous Recombination
Genetics (clinical)
Genetics
Protein Stability
Cullin Proteins
Adaptation
Physiological
Enzymes
3. Good health
Cell biology
Nucleic acids
Cell Processes
Helicases
Protein Binding
Research Article
DNA Replication
Saccharomyces cerevisiae Proteins
lcsh:QH426-470
Genes
Fungal
Immunoblotting
Molecular Probe Techniques
Saccharomyces cerevisiae
Biology
Research and Analysis Methods
03 medical and health sciences
Replication factor C
Control of chromosome duplication
Minichromosome maintenance
Multienzyme Complexes
Molecular Biology Techniques
Molecular Biology
Ecology
Evolution
Behavior and Systematics
Biology and life sciences
DNA replication
Proteins
DNA
Cell Biology
Ubiquitin Ligases
Protein Structure
Tertiary
lcsh:Genetics
030104 developmental biology
Mutation
Enzymology
DNA damage
Origin recognition complex
Replisome
030217 neurology & neurosurgery
Zdroj: PLoS Genetics, Vol 12, Iss 2, p e1005843 (2016)
Europe PubMed Central
Plos Genetics
PLoS Genetics, 12 (2)
PLoS genetics
PLoS Genetics
ISSN: 1553-7404
1553-7390
Popis: Faithful DNA replication and repair requires the activity of cullin 4-based E3 ubiquitin ligases (CRL4), but the underlying mechanisms remain poorly understood. The budding yeast Cul4 homologue, Rtt101, in complex with the linker Mms1 and the putative substrate adaptor Mms22 promotes progression of replication forks through damaged DNA. Here we characterized the interactome of Mms22 and found that the Rtt101Mms22 ligase associates with the replisome progression complex during S-phase via the amino-terminal WD40 domain of Ctf4. Moreover, genetic screening for suppressors of the genotoxic sensitivity of rtt101Δ cells identified a cluster of replication proteins, among them a component of the fork protection complex, Mrc1. In contrast to rtt101Δ and mms22Δ cells, mrc1Δ rtt101Δ and mrc1Δ mms22Δ double mutants complete DNA replication upon replication stress by facilitating the repair/restart of stalled replication forks using a Rad52-dependent mechanism. Our results suggest that the Rtt101Mms22 E3 ligase does not induce Mrc1 degradation, but specifically counteracts Mrc1’s replicative function, possibly by modulating its interaction with the CMG (Cdc45-MCM-GINS) complex at stalled forks.
Author Summary Post-translational protein modifications, such as ubiquitylation, are essential for cells to respond to environmental cues. In order to understand how eukaryotes cope with DNA damage, we have investigated a conserved E3 ubiquitin ligase complex required for the resistance to carcinogenic chemicals. This complex, composed of Rtt101, Mms1 and Mms22 in budding yeast, plays a critical role in regulating the fate of stalled DNA replication. Here, we found that the Rtt101Mms22 E3 ubiquitin ligase complex interacts with the replisome during S-phase, and orchestrates the repair/restart of DNA synthesis after stalling by activating a Rad52-dependent homologous recombination pathway. Our findings indicate that Rtt101Mms22 specifically counteracts the replicative activity of Mrc1, a subunit of the fork protection complex, possibly by modulating its interaction with the CMG (Cdc45-MCM-GINS) helicase complex upon fork stalling. Altogether, our study unravels a functional protein cluster that is essential to understand how eukaryotic cells cope with DNA damage during replication and, thus deepens our knowledge of the biology that underlies carcinogenesis.
Databáze: OpenAIRE
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