Homologous recombination pathway protein (HR protein)

The term "Homologous recombination pathway proteins" refers to a group of proteins functioning together in the homologous recombination (HR) pathway, a template-based mechanism for repair of double-strand DNA breaks and interstrand crosslinks to maintain genomic integrity[1][5][6]. The pathway includes recombinases (e.g., RAD51 in eukaryotes, RecA in bacteria), tumor suppressor proteins (BRCA1, BRCA2), end resection machinery (MRN complex: MRE11, RAD50, NBS1), and accessory factors such as helicases, topoisomerases, and polymerases[5][1][4]. These proteins sequentially coordinate detection, resection, homology search, strand invasion, and repair DNA synthesis. Errors or deficiency in HR components result in genomic instability, promoting oncogenesis (notably breast and ovarian cancers with BRCA mutations)[1][5]. While HR pathway proteins themselves are multi-component and not typically direct therapeutic targets, their status is central in guiding cancer therapies that exploit synthetic lethality, particularly the use of PARP inhibitors in tumors with HR deficiencies (e.g., BRCA-deficient cancers)[1][5]. HR pathway activity or dysfunction is also a critical biomarker for predicting response to DNA-damaging chemotherapies and targeted therapies.

Other names

Homologous recombination proteinHR proteinDNA recombination proteinRecombination repair protein

Synthetic lethality (PARP inhibitors in HR-deficient cells) Sensitization to DNA-damaging agents