2M18

Structure of stacked G-quadruplex formed by human TERRA sequence in potassium solution

Summary for 2M18

• Entry DOI: 10.2210/pdb2m18/pdb
• NMR Information: BMRB: 18847
• Descriptor: RNA (5'-R(*GP*GP*GP*UP*UP*AP*GP*GP*GP*U)-3') (1 entity in total)
• Functional Keywords: rna g-quadruplex, human telomeric rna, stacked g-quadruplex, rna
• Total number of polymer chains: 4
• Total formula weight: 13095.92

Authors

Martadinata, H.,Phan, A.T. (deposition date: 2012-11-20, release date: 2013-04-17, Last modification date: 2024-05-15)

Primary citation

Martadinata, H.,Phan, A.T.
Structure of Human Telomeric RNA (TERRA): Stacking of Two G-Quadruplex Blocks in K(+) Solution
Biochemistry, 52:2176-2183, 2013

PubMed Abstract: Telomeric repeat-containing RNAs (TERRA) are transcription products of the telomeres. Human TERRA sequences containing UUAGGG repeats can form parallel-stranded G-quadruplexes. The stacking interaction of such structures was shown to be important for ligand targeting and higher-order arrangement of G-quadruplexes in long TERRA sequences. Here we report on the first high-resolution structure of a stacked G-quadruplex formed by the 10-nucleotide human TERRA sequence r(GGGUUAGGGU) in potassium solution. This structure comprises two dimeric three-layer parallel-stranded G-quadruplex blocks, which stack on each other at their 5'-ends. The adenine in each UUA loop is nearly coplanar with the 5'-end G-tetrad forming an A·(G·G·G·G)·A hexad, thereby increasing the stacking contacts between the two blocks. Interestingly, this stacking and loop conformation is different from all structures previously reported for the free human TERRA but resembles the structure previously determined for a complex between a human TERRA sequence and an acridine ligand. This stacking conformation is a potential target for drugs that recognize or induce the stacking interface.

PubMed: 23445442
DOI: 10.1021/bi301606u

Experimental method

SOLUTION NMR