System-wide Analysis of SUMOylation Dynamics in Response to Replication Stress Reveals Novel Small Ubiquitin-like Modified Target Proteins and Acceptor Lysines Relevant for Genome Stability.
Mol Cell Proteomics
; 14(5): 1419-34, 2015 May.
Article
em En
| MEDLINE
| ID: mdl-25755297
ABSTRACT
Genotoxic agents can cause replication fork stalling in dividing cells because of DNA lesions, eventually leading to replication fork collapse when the damage is not repaired. Small Ubiquitin-like Modifiers (SUMOs) are known to counteract replication stress, nevertheless, only a small number of relevant SUMO target proteins are known. To address this, we have purified and identified SUMO-2 target proteins regulated by replication stress in human cells. The developed methodology enabled single step purification of His10-SUMO-2 conjugates under denaturing conditions with high yield and high purity. Following statistical analysis on five biological replicates, a total of 566 SUMO-2 targets were identified. After 2 h of hydroxyurea treatment, 10 proteins were up-regulated for SUMOylation and two proteins were down-regulated for SUMOylation, whereas after 24 h, 35 proteins were up-regulated for SUMOylation, and 13 proteins were down-regulated for SUMOylation. A site-specific approach was used to map over 1000 SUMO-2 acceptor lysines in target proteins. The methodology is generic and is widely applicable in the ubiquitin field. A large subset of these identified proteins function in one network that consists of interacting replication factors, transcriptional regulators, DNA damage response factors including MDC1, ATR-interacting protein ATRIP, the Bloom syndrome protein and the BLM-binding partner RMI1, the crossover junction endonuclease EME1, BRCA1, and CHAF1A. Furthermore, centromeric proteins and signal transducers were dynamically regulated by SUMOylation upon replication stress. Our results uncover a comprehensive network of SUMO target proteins dealing with replication damage and provide a framework for detailed understanding of the role of SUMOylation to counteract replication stress. Ultimately, our study reveals how a post-translational modification is able to orchestrate a large variety of different proteins to integrate different nuclear processes with the aim of dealing with the induced DNA damage.
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Base de dados:
MEDLINE
Assunto principal:
Osteoblastos
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Proteínas Recombinantes de Fusão
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Inibidores da Síntese de Ácido Nucleico
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Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina
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Hidroxiureia
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Lisina
Tipo de estudo:
Prognostic_studies
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article