HIV-1 reverse transcription initiation : impact of A-rich loop deletion and M184V substitution and development of novel antiretroviral strategies

Reverse transcription of human immunodeficiency virus type-1 (HIV-1) is primed by cellular tRNALys3, which is selectively packaged into viral particles where it is bound at its 3' terminus to a complementary sequence of viral RNA termed the primer binding site (PBS). In addition to the PBS, other regions within the viral genome also interact with tRNALys3. Initiation of HIV-1 reverse transcription requires specific recognition of the viral genome, tRNA primer, and reverse transcriptase (RT). In this work, we study the important role played by the initiation complex in the initiation of HIV-1 reverse transcription. An "A-rich loop" located upstream of the PBS has been shown to interact with the anticodon loop of tRNALys3 and deletion of this A-rich loop caused diminished viral replication fitness. We have now studied the mechanisms involved in the altered replication capacities of the deletion-containing viruses in the context of both wild type HIV-1 and viruses also containing the M184V substitution in RT. We found that the M184V mutation in RT compromises the ability of deletion-containing viruses to restore wild-type replication. Further biochemical study indicates that both the M184V mutation in RT and deletion of sequences upstream of PBS caused diminished viral replication fitness by compromising the efficiency of reverse transcription initiation. / Since the initiation of DNA synthesis was shown to be a highly specific process, it represents a potential target for the development of novel antiviral agents. We developed strategies for inhibition of the HIV-1 replication via interference with the tRNALys3/viral RNA complex. To target primer tRNALys3, we employed oligodeoxyribonucleotides (ODNs) that are complementary to different parts of the tRNA primer. To target viral RNA, we devised a tRNALys3-like molecule, termed tRNA Lys*, that contained sequence alterations that direct initiation from a region distant from the natural PBS, designated PBS*. PBS* is involved in the formation of the natural tRNA/PBS complex and binding of tRNALys* was shown to interfere specifically with the initiation of reverse transcription. Inhibition of the synthesis of (-) strand strong-stop DNA was achieved successfully with both strategies by interfering with the formation of the initiation complex.

Identiferoai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.84447
Date January 2002
CreatorsWei, Xin, 1971-
ContributorsWainberg, Mark A. (advisor)
PublisherMcGill University
Source SetsLibrary and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada
LanguageEnglish
Detected LanguageEnglish
TypeElectronic Thesis or Dissertation
Formatapplication/pdf
CoverageDoctor of Philosophy (Department of Microbiology and Immunology.)
RightsAll items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated.
Relationalephsysno: 001975674, proquestno: AAINQ88600, Theses scanned by UMI/ProQuest.

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