Structure of the RNA Signal Essential for Translational Frameshifting in HIV-1
Gaudin, C., Mazauric, M.H., Traikia, M., Guittet, E., Yoshizawa, S., Fourmy, D.(2005) J Mol Biol 349: 1024-1035
- PubMed: 15907937 
- DOI: https://doi.org/10.1016/j.jmb.2005.04.045
- Primary Citation of Related Structures:  
1ZC5 - PubMed Abstract: 
Many pathogenic viruses use a programmed -1 translational frameshifting mechanism to regulate synthesis of their structural and enzymatic proteins. Frameshifting is vital for viral replication. A slippery sequence bound at the ribosomal A and P sites as well as a downstream stimulatory RNA structure are essential for frameshifting. Conflicting data have been reported concerning the structure of the downstream RNA signal in human immunodeficiency virus type 1 (HIV-1). Here, the solution structure of the HIV-1 frameshifting RNA signal was solved by heteronuclear NMR spectroscopy. This structure reveals a long hairpin fold with an internal three-nucleotide bulge. The internal loop introduces a bend between the lower and upper helical regions, a structural feature often seen in frameshifting pseudoknots. The NMR structure correlates with chemical probing data. The upper stem rich in conserved G-C Watson-Crick base-pairs is highly stable, whereas the bulge region and the lower stem are more flexible.
Organizational Affiliation: 
Laboratoire de RMN, ICSN-CNRS 1 ave de la terrasse, 91190 Gif-sur-Yvette, France.