A defective proviral DNA with a 2.6-kb deletion of human immunodeficiency virus type 1 (HIV-1) in a persistently HIV-1 infected cell clone

Abstract

A cell line (H2-5) producing defective doughnut-shaped particles of human immunodeficiency virus type I (HIV-1) was found to contain proviral DNA with a large deletion of 2558 bases, corresponding to the 3' half of pol gene, the vif and vpr genes, and the 5' terminal of the tat gene.

Human immunodeficiency virus type 1vif, vpr, andvpu mutants can produce persistently infected cells

“…For a probe, HIV-1 32p-labeled HindIII DNA fragments at nucleotides 531 to 9606 containing almost the entire HIV-1 genome ofpNL 432 were prepared as described previously [11].…”

“…Thus, it is important to determine which HIV-t gene(s) are required for MT-4 cell death. We previously reported that HIV-1 D N A structural analyses of cell clones isolated from MT-4/HIV-1 by Southern blotting revealed deletion at different sites of the proviral HIV-1 DNA, and one cell clone producing defective doughnut-shaped particles (designated as H 2-5) contained proviral D N A with a large deletion of 2558 bases, corresponding to the 3' half of the pol gene, the entire v/f and vpr genes, and the 5' terminal of the tat gene [11]. Here we report the cell killing capacity of HIV-1 vif, vpr, vpu, and n e f m u t a n t viruses in the MT-4 cell system.…”

Cells surviving infection by human immunodeficiency virus type 1: vif or vpu mutants produce non-infectious or markedly less cytopathic viruses

“…DNA and poly(A)* RNA fractions were prepared from cells as previously described (Chomczynski & Sacchi, 1987;Imai et al, 1991). Southern and Northern blot hybridizations were carried out as described previously .…”

Clone B7 cells have a single copy of SIVsmB7 integrated in chromosome 20

“…Thus, clone B7 cells constitutively produce high levels of homogeneous, replication-defective VLP (SIVsmB7). Others laboratories have established cell lines harboring defective proviruses [13,14]. B7 cells are also clonal in nature, and produce non-infectious particles that have been shown to be immunogenic.…”

“…However, the presence of a single, defective proviral genome in the B7 chromosomes strengthens the hypothesis of the faulty reverse transcription. Of interest, chronically infected cells producing Pol-deleted/mutated HIV have been reported by others [13,14]. Nevertheless, the mechanisms by which a Pol/Vpr-defective genome (such as SIVsmB7 DNA) can integrate into the host cell genome have yet to be elucidated.…”