The presence of human immunodeficiency virus type 1 Vpr correlates with a decrease in the frequency of mutations in a plasmid shuttle vector

The human immunodeficiency virus type 1 (HIV-1) Vpr protein induces cell cy cle arrest at the border of G(2) and M similar to the arrest caused by agen ts which damage DNA. We determined whether the presence of Vpr would affect the ability of cells to repair DNA, We developed a shuttle vector system t o analyze the effect of Vpr upon the repair of UV-damaged DNA. Our results demonstrated that the presence of Vpr decreased the rate of deletions in th is system. Of note, cells arrested in G(2) by other genotoxic agents also i ncreased the frequency of DNA repair of UV-damaged shuttle vectors, We did not observe any direct effect of Vpr upon the rate of double-strand break r epair and/or nucleotide excision repair of genomic DNA in cells. Our result s suggest a role for HIV-1 Vpr in altering the frequency of DNA repair, a p roperty which may have importance for HIV-1 replication and pathogenesis.