D York-Higgins | PubMed Health

PubMed1990

Host sequences flanking the HIV provirus.

A conserved property of retroviral proviruses is the presence of a direct repeat in the host DNA immediately flanking the viral sequence; each virus generates a repeat with a characteristic length. By sequencing the viral/host DNA junctions from five HIV-1 proviral clones, we have confirmed that integration of HIV results in the generation of a five basepair direct repeat. A target sequence in uninfected host DNA was analyzed to establish that the five basepair sequence flanking the provirus was present only once prior to integration. Of the five proviruses examined, two were found to have integrated in known repetitive sequence elements of the human genome; one in a Line-1 element and a second in satellite DNA.

Base Sequence↗

PubMed1990

Human immunodeficiency virus type 1 cellular host range, replication, and cytopathicity are linked to the envelope region of the viral genome.

Human immunodeficiency virus type 1 (HIV-1) isolates vary in their in vitro biologic characteristics such as cellular host range, replication kinetics, and cytopathicity. In this study, we molecularly exchanged equivalent regions between two cloned HIV-1 isolates with differing replicative and cytopathic properties. To facilitate generation of recombinant viruses, we used a method involving cotransfection of human monolayer cells with plasmid constructs containing half of the biologically active viral genome. The two halves of the genome were subsequently ligated by intracellular processes to form the complete proviral genome. This method simplifies plasmid construction, since new infectious virus particles can be produced easily from the individual constructs that are correctly ligated in vivo. Results obtained by using recombinant viruses generated in this manner indicate that the ability of HIV to replicate in specific cell types and cytopathicity segregate with the env region of the viral genome.

Amino Acid Sequence↗