Alternative titles; symbols
HGNC Approved Gene Symbol: ABRAXAS1
Cytogenetic location: 4q21.23 Genomic coordinates (GRCh38): 4:83,459,517-83,485,100 (from NCBI)
Using phosphopeptide affinity proteomic analysis, Wang et al. (2007) identified a protein, Abraxas, that directly binds to the BRCT repeats of BRCA1 (113705), essential for tumor suppression, through a phospho-ser-X-X-phe motif. The 409-amino acid ABRA1 protein contains an ABR domain and a coiled-coil domain followed by the phospho-ser-X-X-phe motif at the C-terminal end of the protein. ABRA1 shares 39% amino acid identity in the N-terminal region with ABRO1 (611144), which also contains an ABR domain and a coiled-coil domain.
Wang et al. (2007) found that abraxas binds BRCA1 to the mutual exclusion of BACH1 (602751) and CTIP (604124), forming a third type of BRCA1 complex. Abraxas recruits the ubiquitin-interacting motif (UIM)-containing protein RAP80 (609433) to BRCA1. Both Abraxas and RAP80 were required for DNA damage resistance, G2/M checkpoint control, and DNA repair. RAP80 was required for optimal accumulation of BRCA1 on damaged DNA (foci) in response to ionizing radiation, and the UIM domains alone were capable of foci formation. Wang et al. (2007) concluded that the RAP80-Abraxas complex may help recruit BRCA1 to DNA damage sites in part through recognition of ubiquitinated proteins.
Gross (2014) mapped the FAM175A gene to chromosome 4q21.23 based on an alignment of the FAM175A sequence (GenBank BC039573) with the genomic sequence (GRCh37).
Gross, M. B. Personal Communication. Baltimore, Md. 2/4/2014.
Wang, B., Matsuoka, S., Ballif, B. A., Zhang, D., Smogorzewska, A., Gygi, S. P., Elledge, S. J. Abraxas and RAP80 form a BRCA1 protein complex required for the DNA damage response. Science 316: 1194-1198, 2007. [PubMed: 17525340] [Full Text: https://doi.org/10.1126/science.1139476]