1pjy
From Proteopedia
Solution structure of the HIV-1 frameshift inducing stem-loop RNA
Structural highlights
Publication Abstract from PubMedThe translation of reverse transcriptase and other essential viral proteins from the HIV-1 Pol mRNA requires a programmed -1 ribosomal frameshift. This frameshift is induced by two highly conserved elements within the HIV-1 mRNA: a slippery sequence comprised of a UUUUUUA heptamer, and a downstream stem-loop structure. We have determined the structure of the HIV-1 frameshift inducing RNA stem-loop, using multidimensional heteronuclear nuclear magnetic resonance (NMR) methods. The 22 nucleotide RNA solution structure [root mean squared deviation (r.m.s.d.) = 1.2 A] was determined from 475 nuclear Overhauser effect (NOE)-derived distance restrains, 20 residual dipolar couplings and direct detection of hydrogen bonds via scalar couplings. We find that the frameshift inducing stem-loop is an A-form helix capped by a structured ACAA tetraloop. The ACAA tetraloop is stabilized by an equilateral 5' and 3' stacking pattern, a sheared A-A pair and a cross-strand hydrogen bond. Unexpectedly, the ACAA tetraloop structure is nearly identical to a known tetraloop fold, previously identified in the RNase III recognition site from Saccharomyces cerevisiae. Solution structure of the HIV-1 frameshift inducing stem-loop RNA.,Staple DW, Butcher SE Nucleic Acids Res. 2003 Aug 1;31(15):4326-31. PMID:12888491[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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