This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
4x01
From Proteopedia
S. pombe Ctp1 tetramerization domain
Structural highlights
FunctionCOM1_SCHPO Endonuclease that cooperates with the MRN complex in processing meiotic and mitotic double-strand breaks by allowing the endonucleolytic removal of rec12 from the break sites and ensuring both resection and intrachromosomal association of the broken ends. Required for the formation of RPA-coated single strand DNA adjacent to the DSBs where it functions together with the MRN complex in 5'- 3' resection. Required for the repair of programmed meiotic DSBs. Involved also in an rhp51 recombinase-dependent recombinational repair pathway.[1] [2] [3] [4] Publication Abstract from PubMedCtp1 (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. Tetrameric Ctp1 coordinates DNA binding and DNA bridging in DNA double-strand-break repair.,Andres SN, Appel CD, Westmoreland JW, Williams JS, Nguyen Y, Robertson PD, Resnick MA, Williams RS Nat Struct Mol Biol. 2015 Jan 12. doi: 10.1038/nsmb.2945. PMID:25580577[5] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||||
