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Destabilization of the TAR Hairpin Leads to Extension of the PolyA Hairpin and Inhibition of HIV-1 Polyadenylation

Overview
Journal Retrovirology
Publisher Biomed Central
Specialty Microbiology
Date 2009 Feb 13
PMID 19210761
Citations 10
Authors
Affiliations
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Abstract

Background: Two hairpin structures that are present at both the 5' and 3' end of the HIV-1 RNA genome have important functions in the viral life cycle. The TAR hairpin binds the viral Tat protein and is essential for Tat-mediated activation of transcription. The adjacent polyA hairpin encompasses the polyadenylation signal AAUAAA and is important for the regulation of polyadenylation. Specifically, this RNA structure represses polyadenylation at the 5' side, and enhancer elements on the 3' side overcome this suppression. We recently described that the replication of an HIV-1 variant that does not need TAR for transcription was severely impaired by destabilization of the TAR hairpin, even though a complete TAR deletion was acceptable.

Results: In this study, we show that the TAR-destabilizing mutations result in reduced 3' polyadenylation of the viral transcripts due to an extension of the adjacent polyA hairpin. Thus, although the TAR hairpin is not directly involved in polyadenylation, mutations in TAR can affect this process.

Conclusion: The stability of the HIV-1 TAR hairpin structure is important for the proper folding of the viral RNA transcripts. This study illustrates how mutations that are designed to study the function of a specific RNA structure can change the structural presentation of other RNA domains and thus affect viral replication in an indirect way.

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References
1.
Das A, Harwig A, Vrolijk M, Berkhout B . The TAR hairpin of human immunodeficiency virus type 1 can be deleted when not required for Tat-mediated activation of transcription. J Virol. 2007; 81(14):7742-8. PMC: 1933349. DOI: 10.1128/JVI.00392-07. View

2.
Huthoff H, Berkhout B . Two alternating structures of the HIV-1 leader RNA. RNA. 2001; 7(1):143-57. PMC: 1370064. DOI: 10.1017/s1355838201001881. View

3.
Gilmartin G, Fleming E, Oetjen J . Activation of HIV-1 pre-mRNA 3' processing in vitro requires both an upstream element and TAR. EMBO J. 1992; 11(12):4419-28. PMC: 557016. DOI: 10.1002/j.1460-2075.1992.tb05542.x. View

4.
Brady J, Kashanchi F . Tat gets the "green" light on transcription initiation. Retrovirology. 2005; 2:69. PMC: 1308864. DOI: 10.1186/1742-4690-2-69. View

5.
Berkhout B . Multiple biological roles associated with the repeat (R) region of the HIV-1 RNA genome. Adv Pharmacol. 2000; 48:29-73. DOI: 10.1016/s1054-3589(00)48003-8. View