中文摘要：

G-四链体结构是近年来发现的特殊核酸二级结构，它在体内极易形成，分布十分广泛并且具有重要的生物学功能。研究者们已经在体外检测到G-四链体的存在并解析出其晶体结构，各种检测该结构的方法如特异性荧光探针、抗体等也不断被发现或合成。 G-四链体不仅广泛分布于端粒、启动子区、外显子等具有重要功能的基因区域，在5＇非编码区（5＇UTR ）、内含子区、3＇非编码区（3＇UTR）等也有广泛存在。相应区域的G-四链体参与到端粒延长、DNA复制、转录、减数分裂、基因重组等重要的生命过程，发挥抗肿瘤、抗病毒、抑制血管新生等作用。目前基于G-四链体结构的抗肿瘤药物已经进入临床试验阶段并取得了良好的疗效。 G-四链体结构的内源性调节包括多种内源性蛋白以及碱基的甲基化等，维持其含量与结构的平衡状态。此外，外源性小分子也可对体内G-四链体的平衡状态发挥调节作用。本文将从化学、生物和医学的角度对G-四链体结构的检测方法及其特殊功能和调控进行系统的论述和展望。

英文摘要：

G-quadruplex structure was found recently as a special secondary structure of Nucleic acid.It can be formed easily and widely in vivo and has important biological functions.Researchers have detected the formation of G-quadruplex in vitro and solved its crystal structure by using specific fluorescent probes, antibodies, etc., which are constantly discovered or synthesized.G-quadruplex structures are distributed widely not only in the significantly functional region as telomere, promoter, gene extron, but also in the 5＆#39;untranslated region （5＆#39;UTR） , intron and 3＆#39;flanking region（3＆#39;UTR） of RNA .They play vital roles in the extension of telomeres, DNA replication, transcription, meiosis, recombination, and otherpivotal life processes.Additionally, they can exert anti-tumor, anti-virus, inhibiting angiogenesis and other impor-tant functions.Currently anticancer drugs based on G-quadruplex structure have entered clinical trials and obtained good curative effects.G-quadruplex can be regulated endogenously by the methylation and the interaction with many proteins and stays in a balanced content and morphology.Some exogenous small molecules can also play such regulatory roles.This paper will systematically summarize detection meth-ods, special functions and regulation of G-quadruplex in the fields of chemistry, biology and medicine.