6E8S

Structure of the iMango-III aptamer bound to TO1-Biotin

6E8S の概要

• エントリーDOI: 10.2210/pdb6e8s/pdb
• 分子名称: iMango-III aptamer, 4-[(3-{2-[(2-methoxyethyl)amino]-2-oxoethyl}-1,3-benzothiazol-3-ium-2-yl)methyl]-1-methylquinolin-1-ium, POTASSIUM ION, ... (7 entities in total)
• 機能のキーワード: aptamer, fluorescence, rna, g-quadruplex
• 由来する生物種: synthetic construct
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 25882.81

構造登録者

Trachman, R.J.,Ferre-D'Amare, A.R. (登録日: 2018-07-31, 公開日: 2019-04-17, 最終更新日: 2024-03-13)

主引用文献

Trachman 3rd., R.J.,Autour, A.,Jeng, S.C.Y.,Abdolahzadeh, A.,Andreoni, A.,Cojocaru, R.,Garipov, R.,Dolgosheina, E.V.,Knutson, J.R.,Ryckelynck, M.,Unrau, P.J.,Ferre-D'Amare, A.R.
Structure and functional reselection of the Mango-III fluorogenic RNA aptamer.
Nat. Chem. Biol., 15:472-479, 2019

PubMed Abstract: Several turn-on RNA aptamers that activate small-molecule fluorophores have been selected in vitro. Among these, the ~30 nucleotide Mango-III is notable because it binds the thiazole orange derivative TO1-Biotin with high affinity and fluoresces brightly (quantum yield 0.55). Uniquely among related aptamers, Mango-III exhibits biphasic thermal melting, characteristic of molecules with tertiary structure. We report crystal structures of TO1-Biotin complexes of Mango-III, a structure-guided mutant Mango-III(A10U), and a functionally reselected mutant iMango-III. The structures reveal a globular architecture arising from an unprecedented pseudoknot-like connectivity between a G-quadruplex and an embedded non-canonical duplex. The fluorophore is restrained into a planar conformation by the G-quadruplex, a lone, long-range trans Watson-Crick pair (whose A10U mutation increases quantum yield to 0.66), and a pyrimidine perpendicular to the nucleobase planes of those motifs. The improved iMango-III and Mango-III(A10U) fluoresce ~50% brighter than enhanced green fluorescent protein, making them suitable tags for live cell RNA visualization.

PubMed: 30992561
DOI: 10.1038/s41589-019-0267-9

実験手法

X-RAY DIFFRACTION (2.35 Å)