Complex sentence: The sequential process then recruits two other proteins, replication protein A (RPA), which protects the normal strand, and xeroderma pigmentosum group A (XPA) which isolates the damaged segment on the strand to be cut.
Split into simpler sentences: The sequential process then recruits two other proteins, xeroderma pigmentosum group A (XPA) and replication protein A (RPA). RPA protects the normal strand, and XPA isolates the damaged segment on the strand to be cut.