G-四聯體

(重定向自G四股結構

G-四聯體(英語:G-quadruplexG-tetradsG4-DNA)是一種由富含鳥嘌呤的核酸序列所構成的四股型態。含有經由胡斯坦(Hoogsteen)氫鍵維持穩定,並由鳥嘌呤以正方形方式排列而成的結構。在方形中央有一個單價陽離子(通常是[1]。這種結構可見於DNARNALNA(鎖核酸)與PNA(肽核酸);根據形成四聯體的各股的方向,可能有分子內(intramolecular)、雙分子(bimolecular)或四分子(tetramolecular)等不同類型[2]

在四聯體的結構中,我們可以根據四股的方向,將結構分為平行反平行英语Antiparallel (biochemistry)

Structure of a G-quadruplex. Left: a G-tetrad. Right: an intramolecular G-quadruplex
3D Structure of the intramolecular human telomeric G-quadruplex in potassium solution (PDB ID 2HY9). The backbone is represented by a tube. The center of this structure contains three layers of G-tetrads. The hydrogen bonds in these layers are represented by blue dashed lines.

註釋编辑

  1. ^ Campbell, Nancy H.; Neidle, Stephen. Chapter 4. G-Quadruplexes and Metal Ions. Astrid Sigel, Helmut Sigel and Roland K. O. Sigel (编). Interplay between Metal Ions and Nucleic Acids. Metal Ions in Life Sciences 10. Springer. 2012: 119–1134. doi:10.1007/978-94-007-2172-2_4. 
  2. ^ Bochman, Matthew L.; Paeschke, Katrin; Zakian, Virginia A. DNA secondary structures: stability and function of G-quadruplex structures. Nature Reviews Genetics 13. Nature Publishing Group. 2012: 770–780. doi:10.1038/nrg3296. 

參考文獻编辑

外部連結编辑

四聯體網站编辑

預測G-四聯體的工具编辑