Summary information and primary citation
- PDB-id
-
4nfp;
DSSR-derived features in text and
JSON formats
- Class
- RNA
- Method
- X-ray (1.85 Å)
- Summary
- Crystal structure analysis of the 16mer
gcagncuuaagucugc containing 8-aza-7-deaza-7-ethynyl
adenosine
- Reference
-
Phelps KJ, Ibarra-Soza JM, Tran K, Fisher AJ, Beal PA
(2014): "Click
Modification of RNA at Adenosine: Structure and
Reactivity of 7-Ethynyl- and
7-Triazolyl-8-aza-7-deazaadenosine in RNA." Acs
Chem.Biol., 9, 1780-1787. doi:
10.1021/cb500270x.
- Abstract
- Ribonucleoside analogues bearing terminal alkynes,
including 7-ethynyl-8-aza-7-deazaadenosine (7-EAA), are
useful for RNA modification applications. However, although
alkyne- and triazole-bearing ribonucleosides are in
widespread use, very little information is available on the
impact of these modifications on RNA structure. By solving
crystal structures for RNA duplexes containing these
analogues, we show that, like adenosine, 7-EAA and a
triazole derived from 7-EAA base pair with uridine and are
well-accommodated within an A-form helix. We show that
copper-catalyzed azide/alkyne cycloaddition (CuAAC)
reactions with 7-EAA are sensitive to the RNA secondary
structure context, with single-stranded sites reacting
faster than duplex sites. 7-EAA and its triazole products
are recognized in RNA template strands as adenosine by
avian myoblastosis virus reverse transcriptase. In
addition, 7-EAA in RNA is a substrate for an active site
mutant of the RNA editing adenosine deaminase, ADAR2. These
studies extend our understanding of the impact of these
novel nucleobase analogues and set the stage for their use
in probing RNA structure and metabolism.
