1QES

TANDEM GU MISMATCHES IN RNA, NMR, 30 STRUCTURES

Summary for 1QES

• Entry DOI: 10.2210/pdb1qes/pdb
• Related: 1QET
• Descriptor: RNA (5'-R(*GP*GP*AP*GP*UP*UP*CP*C)-3') (1 entity in total)
• Functional Keywords: ribonucleic acid, g:u mismatch, rna
• Total number of polymer chains: 2
• Total formula weight: 5085.12

Authors

Mcdowell, J.A.,He, L.,Chen, X.,Turner, D.H. (deposition date: 1997-03-04, release date: 1997-06-05, Last modification date: 2024-05-22)

Primary citation

McDowell, J.A.,He, L.,Chen, X.,Turner, D.H.
Investigation of the structural basis for thermodynamic stabilities of tandem GU wobble pairs: NMR structures of (rGGAGUUCC)2 and (rGGAUGUCC)2.
Biochemistry, 36:8030-8038, 1997

PubMed Abstract: The symmetric, tandem GU mismatch motifs, and , which only differ in the mismatch order, have an average difference in thermodynamic stability of 2 kcal/mol at 37 degrees C. Thermodynamic studies of duplexes containing these motifs indicate the effect is largely localized to the mismatches and adjacent base pairs. The three-dimensional structures of two representative duplexes, (rGGAGUUCC)2 and (rGGAUGUCC)2, were determined by two-dimensional NMR and a simulated annealing protocol. Local deviations are similar to other intrahelical GU mismatches with little effect on backbone torsion angles and a slight overtwisting between the base pair 5' of the G of the mismatch and the mismatch itself. Comparisons of the resulting stacking patterns along with electrostatic potential maps suggest that interactions between highly negative electrostatic regions between base pairs may play a role in the observed thermodynamic differences.

PubMed: 9201950
DOI: 10.1021/bi970122c

Experimental method

SOLUTION NMR