A G-quadruplex-containing RNA activates fluorescence in a GFP-like fluorophore.
Nat Chem Biol
; 10(8): 686-91, 2014 Aug.
Article
in En
| MEDLINE
| ID: mdl-24952597
ABSTRACT
Spinach is an in vitro-selected RNA aptamer that binds a GFP-like ligand and activates its green fluorescence. Spinach is thus an RNA analog of GFP and has potentially widespread applications for in vivo labeling and imaging. We used antibody-assisted crystallography to determine the structures of Spinach both with and without bound fluorophore at 2.2-Å and 2.4-Å resolution, respectively. Spinach RNA has an elongated structure containing two helical domains separated by an internal bulge that folds into a G-quadruplex motif of unusual topology. The G-quadruplex motif and adjacent nucleotides comprise a partially preformed binding site for the fluorophore. The fluorophore binds in a planar conformation and makes extensive aromatic stacking and hydrogen bond interactions with the RNA. Our findings provide a foundation for structure-based engineering of new fluorophore-binding RNA aptamers.
Full text:
1
Database:
MEDLINE
Main subject:
RNA
/
G-Quadruplexes
Language:
En
Journal:
Nat Chem Biol
Journal subject:
BIOLOGIA
/
QUIMICA
Year:
2014
Type:
Article
Affiliation country:
United States