title: ATRIP associates with replication protein A-coated ssDNA through multiple interactions.
abstract: The ATR (ATM- and rad3-related)-mediated checkpoint pathway has a crucial role in regulating the cellular responses to DNA damage and DNA-replication stress. ATRIP (ATR-interacting protein), the regulatory partner of ATR, binds directly to replication protein A (RPA)-coated ssDNA and enables the ATR-ATRIP complex to recognize this DNA damage-induced structure. Here, we show that ATRIP associates with RPA-ssDNA through multiple interactions. Two major RPA-ssDNA-interacting domains of ATRIP were mapped to the regions flanking the conserved coiled-coil domain. In contrast to a recent article, we found that ATRIP mutants lacking the N terminus retained the ability to bind to RPA-ssDNA, suggesting that the multiple interactions between ATRIP and RPA-ssDNA may function redundantly in the recruitment of ATR-ATRIP. Unexpectedly, one internal region of ATRIP exhibited affinity to ssDNA, suggesting that ATRIP may interact with ssDNA in the ATRIP-RPA-ssDNA complex. Also, the N terminus of ATRIP associated with RPA-ssDNA in two distinct ways, indicating a dynamic and regulated association between ATRIP and RPA-ssDNA.
authors.affiliation: Massachusetts General Hospital Cancer Center, Charlestown, MA 02129, USA.
authors.forename: Yuka
authors.initials: Y
authors.lastname: Namiki
authors.forename: Lee
authors.initials: L
authors.lastname: Zou
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D002460:Cell Line; D045744:Cell Line, Tumor; D004277:DNA, Single-Stranded / Q000378:metabolism*; D004268:DNA-Binding Proteins; D005090:Exodeoxyribonucleases / Q000378:metabolism*; D006801:Humans; D010446:Peptide Fragments / Q000378:metabolism; D010750:Phosphoproteins / Q000378:metabolism*; D051716:Replication Protein A / Q000378:metabolism*
chemical_list: C521194:ATRIP protein, human; D048868:Adaptor Proteins, Signal Transducing; D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D010446:Peptide Fragments; D010750:Phosphoproteins; D051716:Replication Protein A; D005090:Exodeoxyribonucleases; C429526:three prime repair exonuclease 1