JVI Accepts, published online ahead of print on 21 November 2007

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Mandal, D. Articles by Stoltzfus, C. M. Search for Related Content PubMed PubMed Citation Articles by Mandal, D. Articles by Stoltzfus, C. M.

 Previous Article  |  Next Article 

J. Virol. doi:10.1128/JVI.02295-07
Copyright (c) 2007, American Society for Microbiology and/or the Listed Authors/Institutions. All Rights Reserved.

GAG PROCESSING DEFECT OF HIV-1 INTEGRASE E246 AND G247 MUTANTS IS CAUSED BY ACTIVATION OF AN OVERLAPPING 5' SPLICE SITE

Dibyakanti Mandal, Zehua Feng, and C. Martin Stoltzfus^*

Department of Microbiology, University of Iowa, Iowa City, IA 52242

^* To whom correspondence should be addressed. Email: marty-stoltzfus{at}uiowa.edu.

We have previously described several HIV-1 mutants that are characterized by an excessive RNA splicing phenotype and reduced virus particle production. In one of these mutants (NLD2up), the sequence of 5' splice site D2 was changed to a consensus splice donor site. This splice site overlaps the HIV-1 integrase reading frame and thus, the NLD2up mutant also bears a G to W change at amino acid 247 of the integrase. A previously described E to K mutant at position 246 of the C-terminal domain of the integrase, which resulted ‘g' to ‘a' mutation at +3 position of overlapping splice donor D2 (NLD2A3), was also shown to affect virus particle production and Gag protein processing. By using second-site mutations to revert the excessive splicing phenotype, we show that the effects on Gag protein processing and virus particle production of both the NLD2up and NLD2A3 mutants are caused by excessive viral RNA splicing due to the activation of the overlapping 5' splice site and not to the changes in the integrase protein. Both integrase protein mutations however are lethal for virus infectivity. These studies suggest that changes in the usage of overlapping splice sites may be a possible alternative explanation for defective virus phenotype resulting from changes in protein coding sequences or in nucleotide sequence during codon optimization.

This article has been cited by other articles:

• Mandal, D., Exline, C. M., Feng, Z., Stoltzfus, C. M. (2009). Regulation of vif mRNA Splicing by Human Immunodeficiency Virus Type 1 Requires 5' Splice Site D2 and an Exonic Splicing Enhancer To Counteract Cellular Restriction Factor APOBEC3G. J. Virol. 83: 6067-6078 [Abstract] [Full Text]  
• Exline, C. M., Feng, Z., Stoltzfus, C. M. (2008). Negative and Positive mRNA Splicing Elements Act Competitively To Regulate Human Immunodeficiency Virus Type 1 Vif Gene Expression. J. Virol. 82: 3921-3931 [Abstract] [Full Text]