Structural and inhibition studies of the RNase H function of xenotropic murine leukemia virus-related virus reverse transcriptase

Karen A. Kirby, Bruno Marchand, Yee Tsuey Ong, Tanyaradzwa P. Ndongwe, Atsuko Hachiya, Eleftherios Michailidis, Maxwell D. Leslie, Daniel V. Sietsema, Tracy L. Fetterly, Christopher A. Dorst, Kamalendra Singh, Zhengqiang Wang, Michael A. Parniak, Stefan G. Sarafianos

Research output: Contribution to journalArticlepeer-review

27 Scopus citations

Abstract

RNase H inhibitors (RNHIs) have gained attention as potential HIV-1 therapeutics. Although several RNHIs have been studied in the context of HIV-1 reverse transcriptase (RT) RNase H, there is no information on inhibitors that might affect the RNase H activity of other RTs. We performed biochemical, virological, crystallographic, and molecular modeling studies to compare the RNase H function and inhibition profiles of the gammaretroviral xenotropic murine leukemia virus-related virus (XMRV) and Moloney murine leukemia virus (MoMLV) RTs to those of HIV-1 RT. The RNase H activity of XMRV RT is significantly lower than that of HIV-1 RT and comparable to that of MoMLV RT. XMRV and MoMLV, but not HIV-1 RT, had optimal RNase H activities in the presence of Mn 2+ and not Mg 2+. Using hydroxyl-radical footprinting assays, we demonstrated that the distance between the polymerase and RNase H domains in the MoMLV and XMRV RTs is longer than that in the HIV-1 RT by ∼3.4 Å. We identified one naphthyridinone and one hydroxyisoquinolinedione as potent inhibitors of HIV-1 and XMRV RT RNases H with 50% inhibitory concentrations ranging from ∼0.8 to 0.02 μM. Two acylhydrazones effective against HIV-1 RT RNase H were less potent against the XMRV enzyme. We also solved the crystal structure of an XMRV RNase H fragment at high resolution (1.5 Å) and determined the molecular details of the XMRV RNase H active site, thus providing a framework that would be useful for the design of antivirals that target RNase H.

Original languageEnglish (US)
Pages (from-to)2048-2061
Number of pages14
JournalAntimicrobial agents and chemotherapy
Volume56
Issue number4
DOIs
StatePublished - Apr 2012

Fingerprint

Dive into the research topics of 'Structural and inhibition studies of the RNase H function of xenotropic murine leukemia virus-related virus reverse transcriptase'. Together they form a unique fingerprint.

Cite this