6M0C

Solution NMR Structures of DNA minidumbbell formed by 5'-CTTG CATG-3'.

6M0C の概要

• エントリーDOI: 10.2210/pdb6m0c/pdb
• 分子名称: DNA (5'-D(*CP*TP*TP*GP*CP*AP*TP*G)-3'), SODIUM ION (2 entities in total)
• 機能のキーワード: dna structure, minidumbbell, type ii tetraloop, dna
• 由来する生物種: Homo sapiens
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 2578.53

構造登録者

Ngai, C.K.,Guo, P. (登録日: 2020-02-21, 公開日: 2020-06-17, 最終更新日: 2024-05-01)

主引用文献

Ngai, C.K.,Lam, S.L.,Lee, H.K.,Guo, P.
High-Resolution Structures of DNA Minidumbbells Comprising Type II Tetraloops with a Purine Minor Groove Residue.
J.Phys.Chem.B, 124:5131-5138, 2020

PubMed Abstract: Minidumbbell (MDB) is a newly discovered DNA structure formed by native sequences, which serves as a possible structural intermediate causing repeat expansion mutations in the genome and also a functional structural motif in constructing DNA-based molecular switches. Until now, all the reported MDBs containing two adjacent type II tetraloops were formed by pyrimidine-rich sequences 5'-YYYR YYYR-3' (Y and R represent pyrimidine and purine, respectively), wherein the second and sixth residues folded into the minor groove and interacted with each other. In this study, we have conducted a high-resolution nuclear magnetic resonance (NMR) spectroscopic investigation on alternative MDB-forming sequences and discovered that an MDB could also be formed stably with a purine in the minor groove, which has never been observed in any previously reported DNA type II tetraloops. Our refined NMR solution structures of the two MDBs formed by 5'-CTTG CTG-3' and 5'-CTTG CTG-3' reveal that the sixth purine residue was driven into the minor groove base-base stacking with the second thymine residue and adenine stacked better than guanine. The results of our present research work expand the sequence criteria for the formation of MDBs and shed light to explore the significance of MDBs.

PubMed: 32484672
DOI: 10.1021/acs.jpcb.0c03163

実験手法

SOLUTION NMR