Anti-BARD1 Antibody Picoband®

BRCA1-associated RING domain protein 1 is a protein that in humans is encoded by the BARD1 gene. This gene encodes a protein which interacts with the N-terminal region of BRCA1. In addition to its ability to bind BRCA1 in vivo and in vitro, it shares homology with the 2 most conserved regions of BRCA1: the N-terminal RING motif and the C-terminal BRCT domain. The RING motif is a cysteine-rich sequence found in a variety of proteins that regulate cell growth, including the products of tumor suppressor genes and dominant protooncogenes. This protein also contains 3 tandem ankyrin repeats. The BARD1/BRCA1 interaction is disrupted by tumorigenic amino acid substitutions in BRCA1, implying that the formation of a stable complex between these proteins may be an essential aspect of BRCA1 tumor suppression. This protein may be the target of oncogenic mutations in breast or ovarian cancer. Multiple alternatively spliced transcript variants encoding different isoforms have been found for this gene.

Component of the PAF1 complex (PAF1C) which has multiple functions during transcription by RNA polymerase II and is implicated in regulation of development and maintenance of embryonic stem cell pluripotency. PAF1C associates with RNA polymerase II through interaction with POLR2A CTD non-phosphorylated and 'Ser-2'- and 'Ser-5'-phosphorylated forms and is involved in transcriptional elongation, acting both indepentently and synergistically with TCEA1 and in cooperation with the DSIF complex and HTATSF1. PAF1C is required for transcription of Hox and Wnt target genes. PAF1C is involved in hematopoiesis and stimulates transcriptional activity of KMT2A/MLL1; it promotes leukemogenesis through association with KMT2A/MLL1-rearranged oncoproteins, such as KMT2A/MLL1-MLLT3/AF9 and KMT2A/MLL1-MLLT1/ENL. PAF1C is involved in histone modifications such as ubiquitination of histone H2B and methylation on histone H3 'Lys-4' (H3K4me3) . PAF1C recruits the RNF20/40 E3 ubiquitin-protein ligase complex and the E2 enzyme UBE2A or UBE2B to chromatin which mediate monoubiquitination of 'Lys-120' of histone H2B (H2BK120ub1) ; UB2A/B-mediated H2B ubiquitination is proposed to be coupled to transcription. PAF1C is involved in mRNA 3' end formation probably through association with cleavage and poly (A) factors. In case of infection by influenza A strain H3N2, PAF1C associates with viral NS1 protein, thereby regulating gene transcription. Connects PAF1C with the RNF20/40 E3 ubiquitin-protein ligase complex. Involved in polyadenylation of mRNA precursors. Has oncogenic activity in vivo and in vitro.

1. Daza-Martin, M., Starowicz, K., Jamshad, M., Tye, S., Ronson, G. E., MacKay, H. L., Chauhan, A. S., Walker, A.K., Stone, H. R., Beesley, J. F. J., Coles, J. L., Garvin, A. J., Stewart, G. S., McCorvie, T. J., Zhang, X., Densham, R. M., Morris, J. R. Isomerization of BRCA1-BARD1 promotes replication fork protection. Nature 571: 521-527, 2019. 2. Dong, Y., Hakimi, M.-A., Chen, X., Kumaraswamy, E., Cooch, N. S., Godwin, A. K., Shiekhattar, R. Regulation of BRCC, a holoenzyme complex containing BRCA1 and BRCA2, by a signalosome-like subunit and its role in DNA repair. Molec. Cell 12: 1087-1099, 2003. 3. Irminger-Finger, I., Leung, W.-C., Li, J., Dubois-Dauphin, M., Harb, J., Feki, A., Jefford, C. E., Soriano, J. V., Jaconi, M., Montesano, R., Krause, K.-H. Identification of BARD1 as mediator between proapoptotic stress and p53-dependent apoptosis. Molec. Cell 8: 1255-1266, 2001.

At -20°C for one year from date of receipt. After reconstitution, at 4°C for one month. It can also be aliquotted and stored frozen at -20°C for six months. Avoid repeated freezing and thawing.