Summary information and primary citation
- PDB-id
-
6e7l;
SNAP-derived features in text and
JSON formats
- Class
- RNA
- Method
- X-ray (2.59 Å)
- Summary
- Structure of a dimerized uucg motif
- Reference
-
Montemayor EJ, Virta JM, Hagler LD, Zimmerman SC, Butcher
SE (2019): "Structure
of an RNA helix with pyrimidine mismatches and
cross-strand stacking." Acta
Crystallogr.,Sect.F, 75, 652-656.
doi: 10.1107/S2053230X19012172.
- Abstract
- The structure of a 22-base-pair RNA helix with
mismatched pyrimidine base pairs is reported. The helix
contains two symmetry-related CUG sequences: a
triplet-repeat motif implicated in myotonic dystrophy type
1. The CUG repeat contains a U-U mismatch sandwiched
between Watson-Crick pairs. Additionally, the center of the
helix contains a dimerized UUCG motif with tandem
pyrimidine (U-C/C-U) mismatches flanked by U-G wobble
pairs. This region of the structure is significantly
different from previously observed structures that share
the same sequence and neighboring base pairs. The tandem
pyrimidine mismatches are unusual and display sheared,
cross-strand stacking geometries that locally constrict the
helical width, a type of stacking previously associated
with purines in internal loops. Thus, pyrimidine-rich
regions of RNA have a high degree of structural
diversity.