Characterization of the R263K mutation in HIV-1 integrase that confers low-level resistance to the second-generation integrase strand transfer inhibitor dolutegravir.
Integrase (IN) strand transfer inhibitors (INSTIs) have been developed to inhibit the ability of HIV-1 integrase to irreversibly link the reverse-transcribed viral DNA to the host genome. INSTIs have proven their high efficiency in inhibiting viral replication in vitro and in patients. However, first-generation INSTIs have only a modest genetic barrier to resistance, allowing the virus to escape these powerful drugs through several resistance pathways. Second-generation INSTIs, such as dolutegravir (DTG, S/GSK1349572), have been reported to have a higher resistance barrier, and no novel drug resistance mutation has yet been described for this drug. Therefore, we performed in vitro selection experiments with DTG using viruses of subtypes B, C, and A/G and showed that the most common mutation to emerge was R263K. Further analysis by site-directed mutagenesis showed that R263K does confer low-level resistance to DTG and decreased integration in cell culture without altering reverse transcription. Biochemical cell-free assays performed with purified IN enzyme containing R263K confirmed the absence of major resistance against DTG and showed a slight decrease in 3' processing and strand transfer activities compared to the wild type. Structural modeling suggested and in vitro IN-DNA binding assays show that the R263K mutation affects IN-DNA interactions.
McGill University AIDS Centre, Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec, Canada.
Peter K
PK
Quashie
Thibault
T
Mesplède
Ying-Shan
YS
Han
Maureen
M
Oliveira
Diane N
DN
Singhroy
Tamio
T
Fujiwara
Mark R
MR
Underwood
Mark A
MA
Wainberg
D002460:Cell Line; D024882:Drug Resistance, Viral; D015658:HIV Infections / Q000821:virology; D019427:HIV Integrase / Q000235:genetics* / Q000378:metabolism; D019428:HIV Integrase Inhibitors / Q000494:pharmacology*; D015497:HIV-1 / Q000187:drug effects* / Q000201:enzymology* / Q000235:genetics; D006575:Heterocyclic Compounds, 3-Ring / Q000494:pharmacology*; D006801:Humans; D008958:Models, Molecular; D020125:Mutation, Missense; D010078:Oxazines; D010879:Piperazines; D011728:Pyridones; D000099226:Dolutegravir
D019427:HIV Integrase; D019428:HIV Integrase Inhibitors; D006575:Heterocyclic Compounds, 3-Ring; D010078:Oxazines; D010879:Piperazines; D011728:Pyridones; D000099226:Dolutegravir; C514801:p31 integrase protein, Human immunodeficiency virus 1