Download MendeleyTetrameric Ctp1 coordinates DNA binding and DNA bridging in DNA double-strand-break repair.
Andres, S.N., Appel, C.D., Westmoreland, J.W., Williams, J.S., Nguyen, Y., Robertson, P.D., Resnick, M.A., Williams, R.S.(2015) Nat Struct Mol Biol 22: 158-166
- PubMed: 25580577
- DOI: https://doi.org/10.1038/nsmb.2945
- Primary Citation of Related Structures:
4X01 - PubMed Abstract:
Ctp1 (also known as CtIP or Sae2) collaborates with Mre11-Rad50-Nbs1 to initiate repair of DNA double-strand breaks (DSBs), but its functions remain enigmatic. We report that tetrameric Schizosaccharomyces pombe Ctp1 contains multivalent DNA-binding and DNA-bridging activities. Through structural and biophysical analyses of the Ctp1 tetramer, we define the salient features of Ctp1 architecture: an N-terminal interlocking tetrameric helical dimer-of-dimers (THDD) domain and a central intrinsically disordered region (IDR) linked to C-terminal 'RHR' DNA-interaction motifs. The THDD, IDR and RHR are required for Ctp1 DNA-bridging activity in vitro, and both the THDD and RHR are required for efficient DSB repair in S. pombe. Our results establish non-nucleolytic roles of Ctp1 in binding and coordination of DSB-repair intermediates and suggest that ablation of human CtIP DNA binding by truncating mutations underlie the CtIP-linked Seckel and Jawad syndromes.
Organizational Affiliation:
Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, US National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina, USA.
