Adeno-associated virus replication protein (Rep)

The Adeno-associated virus (AAV) replication (Rep) protein is a multifunctional non-structural protein essential for the AAV life cycle (UniProt: P03132). It is encoded by the rep gene, which produces four distinct isoforms—Rep78, Rep68, Rep52, and Rep40—through alternative promoters and splicing (PubMed: 12610125). The larger isoforms (Rep78/68) possess site-specific endonuclease and helicase activities, enabling them to recognize viral inverted terminal repeats (ITRs) and the human AAVS1 integration site on chromosome 19 (PubMed: 15596518). The smaller isoforms (Rep52/40) function as ATP-dependent helicases involved in translocating viral genomes into capsids. In the context of biotechnology, Rep is a central component in the manufacturing of recombinant AAV (rAAV) vectors for gene therapy, though its inherent cytotoxicity poses challenges for stable cell line development (PubMed: 28636473). Research also explores Rep as a target for antiviral strategies or as a tool for site-specific gene addition.

Other names

Rep78Rep68Rep52Rep40AAV Rep proteinNon-structural protein RepReplication protein

Rep proteins facilitate viral genome replication by binding to the Inverted Terminal Repeats (ITRs) and creating a site-specific nick at the terminal resolution site (trs) via endonuclease activity, followed by DNA unwinding via helicase activity (PubMed: 15596518).