摘要
以UNCG、GNRA、CUUG(N=A、U、C或G,R=G或A)为端环能够形成稳定的、保守的发夹结构。高分辨率的溶液结构、晶体结构和计算机模拟等方法从原子水平上解析了这些发夹特殊的结构特征。在体内,它们发挥着重要的生物学功能:在折叠过程中作为折叠的起始位置帮助组织RNA分子正确折叠;与核酸受体结合参与三级相互作用;与蛋白质发生相互作用;阻止逆转录酶的延伸等等。另外,由于C(UUCG)G发夹极其稳定的特征,在体外RNA分子的实验测定中它还是稳定核酸结构的理想工具。这些稳定的发夹广泛分布于体内rRNA、催化RNA和非编码mRNA中。但在对人类编码区mRNA结构特征的研究当中,却未发现C(UUCG)G发夹。
RNA hairpins containing UNCG,GNRA,CUUG(N = A,U,C or G, R= G or A)loops are unusually thermodynamic stable and conserved nucleic acid hairpins. Structural features of these tetraloops have been investigated by NMR, X - ray diffraction and molecular dynamics, They have very important function in vivo: stable RNA hairpins define nucleation sites for folding,determine tertiary interactions in RNA, are recognized by UNA - binding proteins, and can stop UNA synthesis by reverse transcriptase. In addition the high thermodynamic stability of C( UUCG)G hairpins makes them ideal tools for stabilizing nucleic acid structure. They are frequently occurring hairpins in ribosomal RNAs,catalytic RNAs.and non - codon mRNAs. However, UUCG is still not found in mRNA coding regions.
出处
《生物信息学》
2004年第1期35-40,共6页
Chinese Journal of Bioinformatics
基金
国家自然科学基金项目(重大研究计划面上项目:90208018
地区:30160036)
国家自然科学基金数学天元基金项目(重点:A0324101)
关键词
热力学稳定
发夹结构
UNCG环
GNRA环
thermodynamic stable
hairpin structure
UNCG tetraloop
GNRA tetraloop
