Formation of adeno-associated virus circular genomes is differentially regulated by adenovirus E4 ORF6 and E2a gene expression

Citation
Ds. Duan et al., Formation of adeno-associated virus circular genomes is differentially regulated by adenovirus E4 ORF6 and E2a gene expression, J VIROLOGY, 73(1), 1999, pp. 161-169
Citations number
30
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Microbiology
Journal title
JOURNAL OF VIROLOGY
ISSN journal
0022-538X → ACNP
Volume
73
Issue
1
Year of publication
1999
Pages
161 - 169
Database
ISI
SICI code
0022-538X(199901)73:1<161:FOAVCG>2.0.ZU;2-R
Abstract
A central feature of the adeno-associated virus (AAV) latent life cycle is persistence in the form of both integrated and episomal genomes. However, t he molecular processes associated with episomal long-term persistence of AA V genomes are only poorly understood, To investigate these mechanisms, we h ave utilized a recombinant AAV (rAAV) shuttle vector to identify circular A AV intermediates from transduced HeLa cells and primary fibroblasts. The un ique structural features exhibited by these transduction intermediates incl uded circularized monomer and dimer virus genomes in a head-to tail array, with associated specific base pair alterations in the 5' viral D sequence. In HeLa cells, the abundance and stability of AAV circular intermediates we re augmented by adenovirus expressing the E2a gene product. In the absence of E2a, adenovirus expressing the E4 open reading frame 6 gene product decr eased the abundance of AAV circular intermediates, favoring instead the lin ear replication form monomer (Rf(m)) and dimer (Rf(d)) structures. In summa ry, the formation of AAV circular intermediates appears to represent a new pathway for AAV genome conversion, which is consistent with the head-to-tai l concatemerization associated with latent-phase persistence of rAAV, A bet ter under standing of this pathway may increase the utility of rAAV vectors for gene therapy.