Analytical ultracentrifugation is a powerful biophysical tool that provides information about G-quadruplex structure, stability, and binding reactivity. This chapter provides a simplified explanation of the method, along with examples of how it can be used to characterize G4 formation and to monitor small-molecule binding.
Precise control of Cas12a activity is essential for the improvement of the detection limit of clinical diagnostics and the minimization of errors. This study addresses the challenge of controlling Cas12a activity, especially in the context of nucleic acid detection where the inherent incompatibility between isothermal amplification and CRISPR reactions complicates accurate diagnostics. An RNA G-quadruplex (RG4) structure at the 5' end of crRNA is introduced to modulate Cas12a activity accurately without the need for chemical modifications.
Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, Jilin 130022, P. R. China.
G-quadruplexes (G4s), as an important type of non-canonical nucleic acid structure, have received much attention because of their regulations of various biological processes in cells. Identifying G4s-protein interactions is essential for understanding G4s-related biology. However, current strategies for exploring G4 binding proteins (G4BPs) include pull-down assays in cell lysates or photoaffinity labeling, which are lack of sufficient spatial specificity at the subcellular level.
School of Health Science and Engineering, Shanghai Engineering Research Center of Food Rapid Detection, University of Shanghai for Science and Technology, Shanghai 200093, China. Electronic address:
Aptamer conformations are susceptible to environmental conditions, which makes it difficult to achieve stable targets detection in complex environments with aptasensors. Imprinting strategy was proposed to immobilize the specific conformation of aptamers, aiming to enhance their recognition anti-interference. However, it is mechanistically unclear how the imprinted polymers affect aptamers' recognition, which limits application of the strategy.
Background: Medullary Thyroid Carcinoma (MTC) is closely associated with mutations in the RET proto-oncogene, placing the activated RET protein at the center of MTC pathogenesis. Existing therapeutic solutions, primarily tyrosine kinase inhibitors such as selpercatinib, vandetanib, and cabozantinib, have shown moderate efficacy but are accompanied by increased risks of side effects and resistance. This study unveils a promising avenue using nonactin, a compound historically recognized for its antibacterial properties, targeting the G-quadruplex interactions within the RET proto-oncogene.
Fluorescence detection of DNA and RNA G-quadruplexes (G4s) is a very efficient strategy to assess not only the existence and prevalence of cellular G4s but also their relevance as targets for therapeutic interventions. Among the fluorophores used to this end, turn-on probes are the most interesting since their fluorescence is triggered only upon interaction with their G4 targets, which ensures a high sensitivity and selectivity of detection. We reported on a series of twice-as-smart G4 probes, which are both smart G4 ligands (whose structure is reorganized upon interaction with G4s) and smart fluorescent probes (whose fluorescence is turned on upon interaction with G4s).
