清华大学李景虹团队通过模块组装多功能探针分析（MAMPA）实现单基因RNA G-quadruplexes和G-quadruplexes被占比的单细胞可视化。相关研究成果发表在2021年11月13日出版的《德国应用化学》。

G-quadruplexes（G4s）是一种非标准核酸二级结构，调节多种生物学功能，被认为是癌症治疗的潜在分子靶点。然而，由于缺乏分析方法，单基因G4s的调控机制尚不清楚。

该文中，研究人员开发了一种模块组装多功能探针分析方法（MAMPA），用于可视化单个细胞中单个基因的内源性G4s。两个模块化探针分别识别G4结构和相邻的RNA序列，模块组件能够以高特异性对单个RNA中的G4s进行成像。通过对几个基因中的G4s进行成像，研究人员发现G4s在每个细胞系的不同mRNA中稳定地被G4结合蛋白（G4BPs）占据，并定义了“G4被占比率”。

总之，研究人员证明MAMPA适用于大多数实验情况，并发现G4占位比率有可能成为活细胞G4s研究的一个新参数。

附：英文原文

Title: Single-cell Visualization of Monogenic RNA G-quadruplex and Occupied G-quadruplex Ratio through Module Assembled Multifunctional Probes Assay (MAMPA)

Author: Yicong Dai, Xucong Teng, Jinghong Li

Issue&Volume: 2021-11-13

Abstract: G-quadruplexes (G4s), non-canonical nucleic acid secondary structure, regulate many biological functions and are considered as potential molecular targets for therapeutics of cancers. However, due to the lack of analytical methods, the regulating mechanism of monogenic G4s is still unclear. Here, we developed a Module Assembled Multifunctional Probes Assay (MAMPA) for visualizing endogenous G4s in individual genes in single cells. Two modular probes separately recognize G4 structures and the adjacent RNA sequences, and the module assembly enables imaging of G4s in an individual RNA with high specificity. Through imaging G4s in several individual genes, we found that G4s were steadily occupied by G4 Binding Proteins (G4BPs) in various mRNAs in every cell line and defined “Occupied G4 Ratio”. In all, we demonstrated MAMPA was suitable for most experiment situations and found that Occupied G4 Ratios had the potential to become a new parameter for the study of G4s in living cells.

DOI: 10.1002/anie.202111132

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202111132