HIV-1 reverse transcriptase connection subdomain mutations reduce template RNA degradation and enhance AZT excision
Open Access
- 5 August 2008
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 105 (31) , 10943-10948
- https://doi.org/10.1073/pnas.0804660105
Abstract
We previously proposed that mutations in the connection subdomain (cn) of HIV-1 reverse transcriptase increase AZT resistance by altering the balance between nucleotide excision and template RNA degradation. To test the predictions of this model, we analyzed the effects of previously identified cn mutations in combination with thymidine analog mutations (D67N, K70R, T215Y, and K219Q) on in vitro RNase H activity and AZT monophosphate (AZTMP) excision. We found that cn mutations G335C/D, N348I, A360I/V, V365I, and A376S decreased primary and secondary RNase H cleavages. The patient-derived cns increased ATP- and PPi-mediated AZTMP excision on an RNA template compared with a DNA template. One of 5 cns caused an increase in ATP-mediated AZTMP excision on a DNA template, whereas three cns showed a higher ratio of ATP- to PPi-mediated excision, indicating that some cn mutations also affect excision on a DNA substrate. Overall, the results strongly support the model that cn mutations increase AZT resistance by reducing template RNA degradation, thereby providing additional time for RT to excise AZTMP.Keywords
This publication has 32 references indexed in Scilit:
- Amino Acid Mutation N348I in the Connection Subdomain of Human Immunodeficiency Virus Type 1 Reverse Transcriptase Confers Multiclass Resistance to Nucleoside and Nonnucleoside Reverse Transcriptase InhibitorsJournal of Virology, 2008
- Conservation Patterns of HIV-1 RT Connection and RNase H Domains: Identification of New Mutations in NRTI-Treated PatientsPLOS ONE, 2008
- Mechanisms by Which the G333D Mutation in Human Immunodeficiency Virus Type 1 Reverse Transcriptase Facilitates Dual Resistance to Zidovudine and LamivudineAntimicrobial Agents and Chemotherapy, 2008
- N348I in the Connection Domain of HIV-1 Reverse Transcriptase Confers Zidovudine and Nevirapine ResistancePLoS Medicine, 2007
- Selection of Mutations in the Connection and RNase H Domains of Human Immunodeficiency Virus Type 1 Reverse Transcriptase That Increase Resistance to 3′-Azido-3′-DideoxythymidineJournal of Virology, 2007
- Mutations in Human Immunodeficiency Virus Type 1 RNase H Primer Grip Enhance 3′-Azido-3′-Deoxythymidine ResistanceJournal of Virology, 2007
- Mutations in the connection domain of HIV-1 reverse transcriptase increase 3′-azido-3′-deoxythymidine resistanceProceedings of the National Academy of Sciences, 2007
- HIV-1 Dynamics in Vivo: Virion Clearance Rate, Infected Cell Life-Span, and Viral Generation TimeScience, 1996
- Rapid turnover of plasma virions and CD4 lymphocytes in HIV-1 infectionNature, 1995
- Viral dynamics in human immunodeficiency virus type 1 infectionNature, 1995