G. Goodarzi et al., HOST SITE SELECTION FOR CONCERTED INTEGRATION BY HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 VIRIONS IN-VITRO, Virology, 231(2), 1997, pp. 210-217
Host site selection for full-site integration by human immunodeficienc
y virus type-1 (HIV-1) integrase (IN) from nonionic detergent-lysed vi
rions was investigated. Linear retrovirus-like DNA (469 bp) possessing
3' OH recessed long terminal repeal termini was efficiently inserted
by a bimolecular donor reaction into a supercoiled DNA target (2867 bp
), producing the HlV-1 5-bp host site duplication. Sequence data were
analyzed from 193 donor-target recombinants obtained from the linear 3
.8-kb DNA product. The selection of host target sites appeared randoml
y distributed and was independent of lysis and assay conditions. The f
idelity of the 5-bp duplications in comparison to other size duplicati
ons was highest (94%) with high-salt (300 mM NaCl) lysis of the virion
s and 60 mM NaCl for strand transfer using Mg2+ as the divalent cation
. Base sequence analysis demonstrated some biases in the 5-bp duplicat
ions at the sites of strand transfer and at the immediate host sequenc
es surrounding the duplications. In addition to the observed duplicati
ons, similar to 30% of the recombinants isolated from the linear 3.8-k
b DNA product contained specific and repetitive small-size deletions.
No deletions smaller that 17 bp were observed and the distance between
the deletion sets had a periodicity of similar to 10 bp. The mechanis
ms involved in how HIV-1 IN produces the 5-bp duplications and the rep
etitive host site deletions are discussed. (C) 1997 academic Press.