333D

THE CRYSTAL STRUCTURE OF AN RNA OLIGOMER INCORPORATING TANDEM ADENOSINE-INOSINE MISMATCHES

Summary for 333D

• Entry DOI: 10.2210/pdb333d/pdb
• Descriptor: RNA (5'-R(*CP*GP*CP*AP*IP*GP*CP*G)-3'), CALCIUM ION (3 entities in total)
• Functional Keywords: a-rna, double helix, internal loop, mismatched, rna
• Total number of polymer chains: 1
• Total formula weight: 2605.68

Authors

Carter, R.J.,Baeyens, K.J.,SantaLucia Jr., J.,Turner, D.H.,Holbrook, S.R. (deposition date: 1997-05-20, release date: 1997-10-16, Last modification date: 2024-04-03)

Primary citation

Carter, R.J.,Baeyens, K.J.,SantaLucia, J.,Turner, D.H.,Holbrook, S.R.
The crystal structure of an RNA oligomer incorporating tandem adenosine-inosine mismatches.
Nucleic Acids Res., 25:4117-4122, 1997

PubMed Abstract: The X-ray crystallographic structure of the RNA duplex [r(CGCAIGCG)]2 has been refined to 2.5 A. It shows a symmetric internal loop of two non-Watson-Crick base pairs which form in the middle of the duplex. The tandem A-I/I-A pairs are related by a crystallographic two-fold axis. Both A(anti)-I(anti) mismatches are in a head-to-head conformation forming hydrogen bonds using the Watson-Crick positions. The octamer duplexes stack above one another in the cell forming a pseudo-infinite helix throughout the crystal. A hydrated calcium ion bridges between the 3'-terminal of one molecule and the backbone of another. The tandem A-I mismatches are incorporated with only minor distortion to the backbone. This is in contrast to the large helical perturbations often produced by sheared G-A pairs in RNA oligonucleotides.

PubMed: 9321667
DOI: 10.1093/nar/25.20.4117

Experimental method

X-RAY DIFFRACTION (2.52 Å)