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

Area of Science:

• Virology
• Molecular Biology
• Genetics

Background:

• Retroviruses, like HIV-1, use integrase (IN) to insert their DNA into host chromosomes.
• HIV-1 integration typically favors actively transcribed genes, influenced by host factors like LEDGF.
• Understanding integration site selection is crucial for controlling viral replication and latency.

Purpose of the Study:

• To investigate the impact of a specific point mutation (K258R) in HIV-1 IN on viral integration site distribution.
• To identify potential host factors involved in mediating integration site preference.

Main Methods:

• Deep sequencing to analyze integration sites in viruses with the K258R IN mutation.
• Quantitative PCR and in situ immunofluorescence assays to confirm integration biases.
• Immunoprecipitation studies to identify interacting host factors.

Main Results:

• The K258R IN mutation caused a >10-fold increase in integration frequency into centromeric alpha satellite repeat sequences.
• Confirmation of centromeric integration bias for the K258R mutant virus.
• Identification of host factors that may mediate this centromeric targeting.

Conclusions:

• A single point mutation in HIV-1 IN can dramatically alter integration site preference towards centromeric DNA.
• This altered integration pattern may contribute to the establishment of viral latency and the latent reservoir.
• The K258R mutation's presence in patient data suggests its relevance in natural HIV-1 infection and latency.