ETAA1 acts at stalled replication forks to maintain genome integrity.
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- CitationCopy to clipboard
Bass TE, Luzwick JW, Kavanaugh G, Carroll C, Dungrawala H, Glick GG, Feldkamp MD, Putney R, Chazin WJ, Cortez D
ETAA1 acts at stalled replication forks to maintain genome integrity.
Nat Cell Biol. 2016 Nov;18(11):1185-1195. doi: 10.1038/ncb3415. Epub 2016 Oct 10.
- PubMed ID
- 27723720 [ View in PubMed]
- Abstract
The ATR checkpoint kinase coordinates cellular responses to DNA replication stress. Budding yeast contain three activators of Mec1 (the ATR orthologue); however, only TOPBP1 is known to activate ATR in vertebrates. We identified ETAA1 as a replication stress response protein in two proteomic screens. ETAA1-deficient cells accumulate double-strand breaks, sister chromatid exchanges, and other hallmarks of genome instability. They are also hypersensitive to replication stress and have increased frequencies of replication fork collapse. ETAA1 contains two RPA-interaction motifs that localize ETAA1 to stalled replication forks. It also interacts with several DNA damage response proteins including the BLM/TOP3alpha/RMI1/RMI2 and ATR/ATRIP complexes. It binds ATR/ATRIP directly using a motif with sequence similarity to the TOPBP1 ATR-activation domain; and like TOPBP1, ETAA1 acts as a direct ATR activator. ETAA1 functions in parallel to the TOPBP1/RAD9/HUS1/RAD1 pathway to regulate ATR and maintain genome stability. Thus, vertebrate cells contain at least two ATR-activating proteins.