Ferré-D'Amaré A R, Doudna J A
Department of Molecular Biophysics and Biochemistry, Howard Hughes Medical Institute, Yale University, New Haven, Connecticut 06520-8114, USA.
Annu Rev Biophys Biomol Struct. 1999;28:57-73. doi: 10.1146/annurev.biophys.28.1.57.
An RNA fold is the result of packing together two or more coaxial helical stacks. To date, four RNA folds have been determined at near-atomic resolution by X-ray crystallography: transfer RNA, the hammerhead ribozyme, the P4-P6 domain of the Tetrahymena group I intron, and the hepatitis delta virus ribozyme. All four folds result in RNAs that are considerably more compact than isolated A-form duplexes. These structures illustrate, to varying degrees, three modes of fold stabilization: association of complementary molecular surfaces, stabilization of close RNA packing by binding of cations, and stabilization through pseudoknotting.
RNA折叠是两个或更多同轴螺旋堆积在一起的结果。迄今为止，通过X射线晶体学已在近原子分辨率下确定了四种RNA折叠：转运RNA、锤头状核酶、嗜热四膜虫I组内含子的P4-P6结构域以及丁型肝炎病毒核酶。所有这四种折叠产生的RNA都比分离的A型双链体紧凑得多。这些结构不同程度地说明了三种折叠稳定模式：互补分子表面的缔合、通过阳离子结合稳定紧密的RNA堆积以及通过假结进行稳定。
