NMR structure of the 101-nucleotide core encapsidation signal of the Moloney murine leukemia virus.
The full length, positive-strand genome of the Moloney Murine Leukemia Virus contains a "core encapsidation signal" that is essential for efficient genome packaging during virus assembly. We have determined the structure of a 101-nucleotide RNA that contains this signal (called mPsi) using a novel isotope-edited NMR approach. The method is robust and should be generally applicable to larger RNAs. mPsi folds into three stem loops, two of which (SL-C and SL-D) co-stack to form an extended helix. The third stem loop (SL-B) is connected to SL-C by a flexible, four-nucleotide linker. The structure contains five mismatched base-pairs, an unusual C.CG base-triple platform, and a novel "A-minor K-turn," in which unpaired adenosine bases A340 and A341 of a GGAA bulge pack in the minor groove of a proximal stem, and a bulged distal uridine (U319) forms a hydrogen bond with the phosphodiester of A341. Phylogenetic analyses indicate that these essential structural elements are conserved among the murine C-type retroviruses.
Howard Hughes Medical Institute and Department of Chemistry and Biochemistry, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA.
Victoria
V
D'Souza
Anwesha
A
Dey
Dina
D
Habib
Michael F
MF
Summers
D000818:Animals; D001483:Base Sequence; D051379:Mice; D008958:Models, Molecular; D008969:Molecular Sequence Data; D015394:Molecular Structure; D008979:Moloney murine leukemia virus / Q000737:chemistry* / Q000235:genetics* / Q000502:physiology; D019906:Nuclear Magnetic Resonance, Biomolecular; D009690:Nucleic Acid Conformation; D010802:Phylogeny; D012367:RNA, Viral / Q000737:chemistry* / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid; D019065:Virus Assembly
D012367:RNA, Viral