Rad51BRCAProteinen

Rad51BRCAProteinen is a term used to describe the functional interplay between the Rad51 recombinase and BRCA family proteins in the maintenance of genome integrity during DNA double-strand break repair. It is not a single polypeptide, but a protein complex or network that coordinates homologous recombination.

Rad51 forms nucleoprotein filaments on resected DNA to promote homology search and strand invasion. BRCA1 and BRCA2 regulate this process, with BRCA2 through BRC repeats directly interacting with Rad51 to mediate its loading onto single-stranded DNA, often in concert with PALB2 and other mediators. The term Rad51BRCAProteinen emphasizes this regulatory interface and the dynamic assembly of Rad51 at damage sites.

During S and G2 phases, DNA end resection by the MRN complex and CtIP creates 3' single-stranded DNA overhangs that are coated by RPA, then replaced by Rad51 with BRCA2's help. The Rad51BRCAProteinen network stabilizes the filament, promotes strand invasion into a homologous duplex, and supports DNA synthesis and repair. Proper regulation prevents inappropriate recombination and maintains genome stability.

Clinical relevance: Germline or somatic mutations in BRCA1, BRCA2, or RAD51 family members disrupt this network and increase susceptibility to breast and ovarian cancers and other malignancies. Therapeutic approaches such as PARP inhibitors exploit HR defects.

Evolution and research: The Rad51-BRCA interaction is conserved across eukaryotes. Ongoing research aims to elucidate the precise molecular interfaces and the role of additional regulators in the Rad51BRCAProteinen network.

See also: Homologous recombination, RAD51, BRCA1, BRCA2, PALB2, DNA repair.