Dataset Information

Quantitative analysis of the time-course of viral DNA forms during the HIV-1 life cycle.

ABSTRACT:

Background

HIV-1 DNA is found both integrated in the host chromosome and unintegrated in various forms: linear (DNAL) or circular (1-LTRc, 2-LTRc or products of auto-integration). Here, based on pre-established strategies, we extended and characterized in terms of sensitivity two methodologies for quantifying 1-LTRc and DNAL, respectively, the latter being able to discriminate between unprocessed or 3'-processed DNA.

Results

Quantifying different types of viral DNA genome individually provides new information about the dynamics of all viral DNA forms and their interplay. For DNAL, we found that the 3'-processing reaction was efficient during the early stage of the replication cycle. Moreover, strand-transfer inhibitors (Dolutegravir, Elvitegravir, Raltegravir) affected 3'-processing differently. The comparisons of 2-LTRc accumulation mediated by either strand-transfer inhibitors or catalytic mutation of integrase indicate that 3'-processing efficiency did not influence the total 2-LTRc accumulation although the nature of the LTR-LTR junction was qualitatively affected. Finally, a significant proportion of 1-LTRc was generated concomitantly with reverse transcription, although most of the 1-LTRc were produced in the nucleus.

Conclusions

We describe the fate of viral DNA forms during HIV-1 infection. Our study reveals the interplay between various forms of the viral DNA genome, the distribution of which can be affected by mutations and by inhibitors of HIV-1 viral proteins. In the latter case, the quantification of 3'-processed DNA in infected cells can be informative about the mechanisms of future integrase inhibitors directly in the cell context.

SUBMITTER: Munir S

PROVIDER: S-EPMC3766001 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

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Publications

Quantitative analysis of the time-course of viral DNA forms during the HIV-1 life cycle.

Munir Soundasse S Thierry Sylvain S Subra Frédéric F Deprez Eric E Delelis Olivier O

Retrovirology 20130813

<h4>Background</h4>HIV-1 DNA is found both integrated in the host chromosome and unintegrated in various forms: linear (DNAL) or circular (1-LTRc, 2-LTRc or products of auto-integration). Here, based on pre-established strategies, we extended and characterized in terms of sensitivity two methodologies for quantifying 1-LTRc and DNAL, respectively, the latter being able to discriminate between unprocessed or 3'-processed DNA.<h4>Results</h4>Quantifying different types of viral DNA genome individu ...[more]

PMID: 23938039

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Dataset Information

Quantitative analysis of the time-course of viral DNA forms during the HIV-1 life cycle.

Background

Results

Conclusions

Publications

Quantitative analysis of the time-course of viral DNA forms during the HIV-1 life cycle.

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