Abstract
Retroviruses have evolved mechanisms for transporting their intron-containing RNAs (including genomic and messenger RNAs, which encode virion components) from the nucleus to the cytoplasm of the infected cell. Human retroviruses, such as human immunodeficiency virus (HIV) and human T cell leukemia virus type 1 (HTLV-1), encode the regulatory proteins Rev and Rex, which form a bridge between the viral RNA and the export receptor CRM1. Recent studies show that these transport systems are not only involved in RNA export, but also in the encapsidation of genomic RNA; furthermore, they influence subsequent events in the cytoplasm, including the translation of the cognate mRNA, transport of Gag proteins to the plasma membrane, and the formation of virus particles. Moreover, the mode of interaction between the viral and cellular RNA transport machinery underlies the species-specific propagation of HIV-1 and HTLV-1, forming the basis for constructing animal models of infection. This review article discusses recent progress regarding these issues.
Highlights
Retroviruses have evolved mechanisms for transporting their intron-containing RNAs from the nucleus to the cytoplasm of the infected cell
The human T cell leukemia virus type 1 (HTLV-1) leucine zipper factor (HBZ) gene was identified, which is encoded by a complimentary strand of the HTLV-1 genome, driven by a promoter residing in the 3 long terminal repeat (LTR) (Figure 1)
As the functions of Rex depend largely on the CRM1 protein, we examined whether rat CRM1 (rCRM1) can act as a cofactor for Rex activity as it does in human cells, CRM1 is highly conserved from yeast to mammalians, and hCRM1 can function in yeast cells as an export receptor
Summary
Retroviruses have evolved mechanisms for transporting their intron-containing RNAs (including genomic and messenger RNAs, which encode virion components) from the nucleus to the cytoplasm of the infected cell. Human retroviruses, such as human immunodeficiency virus (HIV) and human T cell leukemia virus type 1 (HTLV-1), encode the regulatory proteins Rev and Rex, which form a bridge between the viral RNA and the export receptor CRM1.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
