Halder Kangkan, Hartig Jörg S
Department of Chemistry, University of Konstanz, Universitätsstrasse 10, D-78457 Konstanz, Germany.
Met Ions Life Sci. 2011;9:125-39. doi: 10.1039/9781849732512-00125.
Opposed to DNA quadruplex sequences, RNA quadruplexes are still less well characterized. On the other hand, RNA quadruplexes are found to be at least as stable as their DNA counterparts. They show the same dependence on metal ions but seem to be much more restricted with respect to the adopted conformations. Other than DNA, which is mostly found to be double-stranded inside cells, RNAs are produced during transcription without its complementary sequence. The absence of a second strand that is able to hybridize and form a duplex makes the folding of RNA quadruplexes a likely event of intramolecular structure formation. Consequently, the formation of RNA quadruplexes in cellular RNAs has recently been suggested and the study of their influence and potential roles in cellular processes has just started. Here we give an overview of the RNA quadruplex field, summarizing issues such as structures, stabilities, and anticipated roles of these interesting four-stranded, guanosine-rich sequences.
与DNA四链体序列相比，RNA四链体的特征仍不太明确。另一方面，人们发现RNA四链体至少与其对应的DNA四链体一样稳定。它们对金属离子表现出相同的依赖性，但在所采用的构象方面似乎受到更多限制。与主要在细胞内呈双链的DNA不同，RNA是在转录过程中产生的，没有其互补序列。由于不存在能够杂交并形成双链体的第二条链，RNA四链体的折叠很可能是分子内结构形成的一个过程。因此，最近有人提出细胞RNA中会形成RNA四链体，并且对其在细胞过程中的影响和潜在作用的研究才刚刚开始。在此，我们对RNA四链体领域进行概述，总结这些有趣的富含鸟苷的四链序列的结构、稳定性和预期作用等问题。
