This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1b3p
From Proteopedia
OCA (Talk | contribs)
(New page: 200px<br /><applet load="1b3p" size="450" color="white" frame="true" align="right" spinBox="true" caption="1b3p" /> '''5'-D(*GP*GP*AP*GP*GP*AP*T)-3''''<br /> ==Ov...)
Next diff →
Revision as of 21:33, 24 November 2007
|
5'-D(*GP*GP*AP*GP*GP*AP*T)-3'
Overview
BACKGROUND: Triplet repeat sequences are of considerable biological, importance as the expansion of such tandem arrays can lead to the onset of, a range of human diseases. Such sequences can self-pair via mismatch, alignments to form higher order structures that have the potential to, cause replication blocks, followed by strand slippage and sequence, expansion. The all-purine d(GGA)n triplet repeat sequence is of particular, interest because purines can align via G.G, A.A and G.A mismatch, formation. RESULTS: We have solved the structure of the uniformly, 13C,15N-labeled d(G1-G2-A3-G4-G5-A6-T7) sequence in 10 mM Na+ solution., This sequence adopts a novel twofold-symmetric duplex fold where, interlocked V-shaped arrowhead motifs are aligned solely via interstrand, G1.G4, G2.G5 and A3.A6 mismatch formation. The tip of the arrowhead motif, is centered about the p-A3-p step, and symmetry-related local, parallel-stranded duplex domains are formed by the G1-G2-A3 and G4-G5-A6, segments of partner strands. CONCLUSIONS: The purine-rich (GGA)n triplet, repeat sequence is dispersed throughout the eukaryotic genome. Several, features of the arrowhead duplex motif for the (GGA)2 triplet repeat, provide a unique scaffold for molecular recognition. These include the, large localized bend in the sugar-phosphate backbones, the segmental, parallel-stranded alignment of strands and the exposure of the, Watson-Crick edges of several mismatched bases.
About this Structure
1B3P is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
Interlocked mismatch-aligned arrowhead DNA motifs., Kettani A, Bouaziz S, Skripkin E, Majumdar A, Wang W, Jones RA, Patel DJ, Structure. 1999 Jul 15;7(7):803-15. PMID:10425682
Page seeded by OCA on Sat Nov 24 23:40:43 2007
