title: SUMOylation of ATRIP potentiates DNA damage signaling by boosting multiple protein interactions in the ATR pathway.
abstract: The ATR (ATM [ataxia telangiectasia-mutated]- and Rad3-related) checkpoint is a crucial DNA damage signaling pathway. While the ATR pathway is known to transmit DNA damage signals through the ATR-Chk1 kinase cascade, whether post-translational modifications other than phosphorylation are important for this pathway remains largely unknown. Here, we show that protein SUMOylation plays a key role in the ATR pathway. ATRIP, the regulatory partner of ATR, is modified by SUMO2/3 at K234 and K289. An ATRIP mutant lacking the SUMOylation sites fails to localize to DNA damage and support ATR activation efficiently. Surprisingly, the ATRIP SUMOylation mutant is compromised in the interaction with a protein group, rather than a single protein, in the ATR pathway. Multiple ATRIP-interacting proteins, including ATR, RPA70, TopBP1, and the MRE11-RAD50-NBS1 complex, exhibit reduced binding to the ATRIP SUMOylation mutant in cells and display affinity for SUMO2 chains in vitro, suggesting that they bind not only ATRIP but also SUMO. Fusion of a SUMO2 chain to the ATRIP SUMOylation mutant enhances its interaction with the protein group and partially suppresses its localization and functional defects, revealing that ATRIP SUMOylation promotes ATR activation by providing a unique type of protein glue that boosts multiple protein interactions along the ATR pathway.
authors.affiliation: Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, Massachusetts 02129, USA;
authors.forename: Ching-Shyi
authors.initials: CS
authors.lastname: Wu
authors.affiliation: Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, Massachusetts 02129, USA;
authors.forename: Jian
authors.initials: J
authors.lastname: Ouyang
authors.affiliation: Division of Molecular Radiation Biology, Department of Radiation Oncology, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA;
authors.forename: Eiichiro
authors.initials: E
authors.lastname: Mori
authors.affiliation: Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, Massachusetts 02129, USA;
authors.forename: Hai Dang
authors.initials: HD
authors.lastname: Nguyen
authors.affiliation: Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, Massachusetts 02129, USA;
authors.forename: Alexandre
authors.initials: A
authors.lastname: Maréchal
authors.affiliation: Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, Massachusetts 02129, USA;
authors.forename: Alexander
authors.initials: A
authors.lastname: Hallet
authors.affiliation: Division of Molecular Radiation Biology, Department of Radiation Oncology, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA;
authors.forename: David J
authors.initials: DJ
authors.lastname: Chen
authors.affiliation: Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, Massachusetts 02129, USA; Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA.
authors.forename: Lee
authors.initials: L
authors.lastname: Zou
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D064007:Ataxia Telangiectasia Mutated Proteins / Q000378:metabolism; D004249:DNA Damage; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004789:Enzyme Activation; D057809:HEK293 Cells; D006367:HeLa Cells; D006801:Humans; D011485:Protein Binding / Q000235:genetics; D021381:Protein Transport; D015398:Signal Transduction; D058207:Sumoylation; D044763:Ubiquitin-Conjugating Enzymes / Q000378:metabolism; D000098843:Ubiquitin-Conjugating Enzyme UBC9
chemical_list: C521194:ATRIP protein, human; D048868:Adaptor Proteins, Signal Transducing; D004268:DNA-Binding Proteins; D044763:Ubiquitin-Conjugating Enzymes; C576597:ATR protein, human; D064007:Ataxia Telangiectasia Mutated Proteins; D000098843:Ubiquitin-Conjugating Enzyme UBC9
keywords: ATR; ATRIP; SUMOylation; checkpoint