Structural highlights
Function
[BRCA1_RAT] E3 ubiquitin-protein ligase that specifically mediates the formation of 'Lys-6'-linked polyubiquitin chains and plays a central role in DNA repair by facilitating cellular responses to DNA damage. It is unclear whether it also mediates the formation of other types of polyubiquitin chains. The E3 ubiquitin-protein ligase activity is required for its tumor suppressor function. The BRCA1-BARD1 heterodimer coordinates a diverse range of cellular pathways such as DNA damage repair, ubiquitination and transcriptional regulation to maintain genomic stability. Regulates centrosomal microtubule nucleation. Required for normal cell cycle progression from G2 to mitosis. Required for appropriate cell cycle arrests after ionizing irradiation in both the S-phase and the G2 phase of the cell cycle. Involved in transcriptional regulation of P21 in response to DNA damage. Required for FANCD2 targeting to sites of DNA damage. May function as a transcriptional regulator. Inhibits lipid synthesis by binding to inactive phosphorylated ACACA and preventing its dephosphorylation. Contributes to homologous recombination repair (HRR) via its direct interaction with PALB2, fine-tunes recombinational repair partly through its modulatory role in the PALB2-dependent loading of BRCA2-RAD51 repair machinery at DNA breaks. Component of the BRCA1-RBBP8 complex which regulates CHEK1 activation and controls cell cycle G2/M checkpoints on DNA damage via BRCA1-mediated ubiquitination of RBBP8 (By similarity).
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Brca1 C-terminal (BRCT) domains are a common protein-protein interaction motif in proteins involved in the DNA damage response and DNA repair. The DNA-damage response protein 53BP1 has two BRCT domains that bind to the DNA-binding domain of p53. The 53BP1 tandem-BRCT region is homologous to the tandem-BRCT region of Brca1, which is involved in double-strand break repair and homologous recombination and which binds BACH1, a member of the DEAH helicase family. Here we report the structures of a human 53BP1-p53 complex and of the rat Brca1 BRCT repeats. The 53BP1-p53 structure shows that the two BRCT repeats are arranged tandemly and pack extensively through an interface that also involves the inter-repeat linker. The first BRCT repeat and the linker together bind p53 on a region that overlaps with the DNA-binding surface of p53 and involves p53 residues that are mutated in cancer and are important for DNA binding. Comparison with the structure of the tandem-BRCT region of Brca1 shows a remarkable conservation of the repeat arrangement and of the inter-BRCT repeat interface. Analysis of human BRCA1 tumor-derived mutations and conservation identifies a potential protein-binding site that we show through mutagenesis is involved in BACH1 binding. The BACH1-binding region of Brca1 consists of a unique insertion in the first BRCT repeat and the inter-repeat linker and is analogous to the region of 53BP1 that binds p53.
Structure of the 53BP1 BRCT region bound to p53 and its comparison to the Brca1 BRCT structure.,Joo WS, Jeffrey PD, Cantor SB, Finnin MS, Livingston DM, Pavletich NP Genes Dev. 2002 Mar 1;16(5):583-93. PMID:11877378[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Joo WS, Jeffrey PD, Cantor SB, Finnin MS, Livingston DM, Pavletich NP. Structure of the 53BP1 BRCT region bound to p53 and its comparison to the Brca1 BRCT structure. Genes Dev. 2002 Mar 1;16(5):583-93. PMID:11877378 doi:http://dx.doi.org/10.1101/gad.959202
