Residues 384–454 of RAG-1 comprise a nonamer-binding region (NBR) that specifically binds the conserved monomer (9 nucleotides) of the RSS and the central domain (amino acids 528–760) of RAG-1 binds specifically to the RSS heptamer. The core region of RAG-2 is predicted to form a six-bladed beta-propeller structure that appears less specific than RAG-1 for its target.
The nonamer-binding region (NBR) in RAG-1, located in residues 384–454, specifically binds the conserved monomer of the RSS. The central domain of RAG-1, spanning amino acids 528–760, also binds specifically to the RSS heptamer. In contrast, the core region of RAG-2 is predicted to form a six-bladed beta-propeller structure that exhibits less specificity for its target.