AAV1-tMCK-GFP

Adeno-associated viruses are non-enveloped, helper-dependent parvoviruses with an icosahedral capsid structure of approximately 25 nm in diameter. AAV encapsidates a genome of approximately 4.7 kb flanked by approximately 145 bp of inverted terminal repeats (ITRs) at the 5′ and 3′ ends. The wild-type AAV (wtAAV) genome is a linear single-stranded DNA consisting of two open reading frames (ORFs). The AAV ORFs encode four replication proteins (Rep) and three capsid proteins (Cap/VP) as well as an assembly activation protein (AAP). In addition, wtAAV requires co-infection with adenovirus or herpes simplex virus (HSV) for successful replication and production of viable AAV particles.

Three advances have facilitated the use of AAV as a recombinant vector for gene transfer applications: (a) the ability to pseudotype AAV vectors by using AAV capsids of either natural or synthetic origin; (b) the cloning and characterization of adenoviral helper genes that are minimally required to produce infectious AAV particles; and (c) the understanding that the ITRs are the only cis-acting molecular features required for successful transgene packaging within the AAV capsid. These simplified components are now used to make recombinant AAV (rAAV) vectors, packaging a variety of promoter elements and transgene cassettes for different gene transfer applications.