Anti-BRCC3 Antibody

A zinc-dependent JAMM/MPN+ metalloprotease, BRCC3 (also called BRCC36) serves as the catalytic subunit of the BRCA1-A complex and the related BRISC complex, where its isopeptidase activity selectively cleaves K63-linked polyubiquitin chains from substrates such as histone H2A at DNA double-strand breaks. The unconjugated rabbit polyclonal antibody from Antibodies.com is supplied as a 100 µl IgG preparation raised against a recombinant fusion protein encoding amino acids 1–316 of human BRCC3 (NP_077308.1) and is affinity-purified for Western blot detection of endogenous BRCC3 across human, mouse, and rat samples, producing an expected band at approximately 33–36 kDa.

The active-site architecture of BRCC3 features two histidines (H122 and H124) and an aspartate (D135) that coordinate a catalytic zinc atom, allowing the enzyme to hydrolyze isopeptide bonds within K63-linked polymers while leaving other chain linkages untouched. In the nucleus, the BRCA1-A complex uses BRCC3 activity to edit ubiquitin signals deposited by the E3 ligases RNF8 and RNF168, dampen excessive end resection, and redistribute BRCA1 toward the periphery of damage foci, favoring non-homologous end joining over hyperactive homologous recombination. Loss of BRCC3 activity disrupts ionizing radiation–induced focus formation, perturbs recruitment of RAP80 and ABRAXAS, and accelerates 53BP1 redistribution on chromatin.

Recommended for immunoblotting at a working dilution of 1:500 to 1:2000 from the supplied vial, this reagent supports research into K63-linked deubiquitination events, BRCA1-A and BRISC complex assembly, the cellular response to ionizing radiation and replication stress, and chromatin-associated signaling in nuclear fractions. Investigators studying BRISC-mediated immune regulation, hematopoietic control, or metabolic signaling through SHMT2 association can likewise monitor endogenous BRCC3 protein levels in appropriate cell and tissue models.