BRCA1 Associated RING Domain Protein 1

**Semantic type:** Amino Acid, Peptide, or Protein|Biologically Active Substance

**Definition:** Encoded by human BARD1 Gene, nuclear BARD-1 Protein contains a RING zinc finger, three tandem ANK repeats, and two BRCT domains. BARD-1 heterodimerizes with BRCA1 via its N-terminal region and interacts with CSTF-50. BARD1/CSTF1 interacts with RNA Polymerase-2, which may inhibit pre-mRNA cleavage or polyadenylation. BARD-1/RNA Polymerase-2 holoenzyme may sense DNA damage; inhibition by CSTF1 may prevent erroneous polyadenylation of such RNAs. Processed during apoptosis, BARD-1 may mediate apoptosis; homodimers are more susceptible to proteolytic cleavage than BARD1/BRCA1. BARD1/BRCA1 interaction is disrupted by tumorigenic amino acid substitutions in BRCA1; a stable BARD1/BRCA1 complex may be essential to BRCA1 tumor suppression. BARD-1 defects are found in primary breast, ovarian and uterine cancers. (from Swiss-Prot Q99728, OMIM 601593, and NCI)

**Synonyms:** - BARD1 Protein - BRCA1 Associated RING Domain 1 - BRCA1-Associated RING Domain 1