A point mutation in HIV-1 integrase redirects proviral integration into centromeric repeats

Abstract

Retroviruses utilize the viral integrase (IN) protein to integrate a DNA copy of their genome into the host chromosomal DNA. HIV-1 integration sites are highly biased towards actively transcribed genes, likely mediated by binding of the IN protein to specific host factors, particularly LEDGF, located at these gene regions. We here report a dramatic redirection of integration site distribution induced by a single point mutation in HIV-1 IN. Viruses carrying the K258R IN mutation exhibit more than a 25-fold increase in integrations into centromeric alpha satellite repeat sequences, as assessed by both deep sequencing and qPCR assays. Immunoprecipitation studies identified host factors that uniquely bind to the mutant IN protein and thus may account for the novel bias for integration into centromeres. Centromeric integration events are known to be enriched in the latent reservoir of infected memory T cells, as well as in patients who control viral replication without intervention (so-called elite controllers). The K258R point mutation in HIV-1 IN reported in this study has also been found in databases of latent proviruses found in patients. The altered integration site preference induced by this mutation has uncovered a hidden feature of the establishment of viral latency and control of viral replication.