《生命科学》 2009, 21(1): 72-75

Z-DNA及其生物学功能

汤雅男，杨　攀，胡成钰*

南昌大学生命科学学院，南昌 330031

摘　要：摘　要：Z-DNA是一种处于高能状态、不稳定的DNA分子构象。形成Z-DNA的原因有很多：首先，转录过程中，移动的RNA聚合酶在模板DNA的5{$39}端产生负超螺旋扭曲力，导致Z-DNA的形成；其次，含有d(GC)n序列的核酸分子在高浓度的NaCl、[Co(NH3)6]2+盐溶液中也能够形成Z-DNA；最后，化学修饰也可以使DNA产生稳定的Z-DNA。Z-DNA是在体外首先发现的，但随着研究的不断深入，发现Z-DNA在体内也广泛存在并可能具有功能的多样性，包括参与基因表达调控、染色体断裂、基因重组、抗病毒、病毒发生等生物学过程。
关键词：Z-DNA；基因表达；Z-DNA结合蛋白；干扰素系统

Z-DNA and its biological function

TANG Ya-nan， YANG Pan， HU Cheng-yu *

College of Life Science， Nanchang University， Nanchang 330031， China

Abstract: Abstract: Z-DNA is an instable and high energy DNA conformation in vivo and it can be formed in many conditions. Firstly， when RNA polymerase is moving on a DNA template， transcription can result in negative supercoiling behind the polymerase， thus facilitating Z-DNA conformation at permissive regions. Secondly， the Z-DNA-conformation which is formed by d(GC)n sequence can also be stabled in high-salt solution of NaCl or [Co(NH3)6]2+ and lastly， the Z-DNA can be formed by covalent modifications. Though Z-DNA was firstly discovered in vitro， recently many evidences revealed that Z-DNA was widely existed and may possessed diversity of function in vivo， including gene expression and regulation， chromosomal breaks， recombination， antivirus defense and virus generation and so on.
Key words: Z-DNA; gene expression; Z-DNA binding protein; IFN system