HIV-1 Rev can specifically interact with MMTV RNA and upregulate gene expression

• Published in: Gene 2005-09, Vol.358, p.17-30
• Main Authors: Dangerfield, John A., Hohenadl, Christine, Egerbacher, Monika, Kodajova, Petra, Salmons, Brian, Günzburg, Walter H.
• Format: Article
• Language: English
• Subjects: Animals; Cercopithecus aethiops; COS Cells; Electrophoretic Mobility Shift Assay; Gene Expression Regulation, Viral - physiology; Gene Products, rev - genetics; Gene Products, rev - metabolism; HIV-1 - genetics; HIV-1 - metabolism; Human immunodeficiency virus 1; Humans; Luciferase; Mammary Tumor Virus, Mouse - genetics; Mammary Tumor Virus, Mouse - metabolism; Mice; Mouse mammary tumor virus; mRNA nuclear export; Protein Binding; Protein–RNA interaction; Regulatory Sequences, Nucleic Acid - physiology; rev Gene Products, Human Immunodeficiency Virus; RNA, Viral - genetics; RNA, Viral - metabolism; Up-Regulation - physiology
• ISSN: 0378-1119; 1879-0038
• DOI: 10.1016/j.gene.2005.05.018

We present evidence that the HIV-1 Rev protein can heterologously regulate expression of the simple beta retrovirus mouse mammary tumour virus (MMTV). Up to 10-fold upregulation was seen in a functional assay system when specific MMTV sequences were substituted for the HIV-1 Rev responsive element (RRE). RNA gel shift analysis showed that purified recombinant Rev could specifically bind to MMTV unique region 3 prime (U3) RNA and that these sequences could compete for wild-type Rev-RRE binding approximately 20-fold more efficiently than a non-specific competitor RNA. Using a combination of in silico and deletion mutation analyses, it was not possible to define any single specific secondary structure responsive to Rev, suggesting that a structure or combination of structures that only form in the context of the complete U3 transcript is/are required to interact with Rev. Taken together, these results suggest that HIV-1 Rev can directly bind to MMTV RNA as well as mediate upregulation of MMTV gene expression.