1mwg
From Proteopedia
STRUCTURE OF RIBONUCLEIC ACID, NMR, MINIMIZED AVERAGE STRUCTURE
Overview
The three-dimensional solution structure of the RNA self-complementary duplex [sequence: see text] was derived from two-dimensional NMR and the iterative relaxation matrix approach. Each GA mismatch forms two hydrogen bonds: A-NH6 to G-O6 and A-N1 to G-NH1 (imino). This is the first three-dimensional RNA structure with imino hydrogen-bonded tandem GA mismatches. This GA structure is totally different from the sheared tandem GA structure in [sequence: see text] which also has two hydrogen bonds: A-N7 to G-NH2 and A-NH6 to G-N3 [SantaLucia, J., Jr., & Turner, D. H. (1993) Biochemistry 32, 12612-12623]. In particular, the sheared and imino GA mismatches produce a narrowing and widening of the backbone, respectively. The results show that substitutions of Watson-Crick base pairs can have dramatic effects on the three-dimensional structures of adjacent non-Watson-Crick paired regions; i.e., the structure depends on sequence context. Thus compensating substitutions in site-directed mutagenesis experiments may not always restore biological activities.
About this Structure
Full crystallographic information is available from OCA.
Reference
Solution structure of (rGCGGACGC)2 by two-dimensional NMR and the iterative relaxation matrix approach., Wu M, Turner DH, Biochemistry. 1996 Jul 30;35(30):9677-89. PMID:8703939 Page seeded by OCA on Sat May 3 01:48:07 2008
