G-quadruplex Amplification
G-quadruplex Amplification - Related Videos
03:38
Aptamer-Based Target Detection Facilitated by a 3-Stage G-Quadruplex Isothermal Exponential Amplification Reaction
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Cited by 1 •
2022
The present protocol demonstrates the use of a fast, 3-stage, aptamer-based exponential amplification assay to detect targets. Sample preparation, signal amplification, and color development are covered to implement this system to recognize the presence of theophylline over that of caffeine.
11:25
A G-quadruplex DNA-affinity Approach for Purification of Enzymatically Active G4 Resolvase1
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Cited by 6 •
2017
G4 Resolvase1 binds to G-quadruplex (G4) structures with the tightest reported affinity for a G4-binding protein and represents the majority of the G4-DNA unwinding activity in HeLa cells. We describe a novel protocol that harnesses the affinity and ATP-dependent unwinding activity of G4-Resolvase1 to specifically purify catalytically active recombinant G4R1.
09:44
Rapid Amplification of cDNA Ends
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2023
Source: Pablo Sanchez Bosch2, Sean Corcoran2 and Katja Brückner1,2,3 1Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research 2Department of Cell and Tissue Biology, 3Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA, USA Rapid Amplification of cDNA Ends (RACE) is a technique that allows amplification of full-length cDNA from mRNA by extending to the 3’ or 5’ end, even without prior knowledge of the sequence (Frohman et al.,...
10:12
Protein Misfolding Cyclic Amplification of Prions
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Cited by 7 •
2012
Protein misfolding cyclic amplification (PMCA) is an in vitro assay for the study of prion conversion and strain and species barriers. It can also be used as a prion detection assay.
02:41
Amplification of a Suicide Plasmid in a Bacterial Host
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2025
Source: Tomás, J. M., et al. Generation of Null Mutants to Elucidate the Role of Bacterial Glycosyltransferases in Bacterial Motility. J. Vis. Exp. (2022).This video demonstrates the initiator-dependent amplification of a suicide plasmid in E. coli. The plasmid, which carries an antibiotic resistance gene, replicates only in the presence of an initiator protein encoded by the host. After electroporation and incubation in recovery medium, the mixture is plated on antibiotic-containing agar.
FAQs
Target recognition promotes the formation or production of guanine-rich DNA or RNA structures. These structures create the G-quadruplex platform needed for downstream signal generation, linking the presence of the target to a detectable molecular output. Because the target-triggered structural change can produce amplified signals, small amounts of material become easier to detect.
Hemin binds to the G-quadruplex and forms a peroxidase-mimicking DNAzyme. This complex provides catalytic activity that converts the structural recognition event into a measurable colorimetric or fluorescent signal. Its role is therefore not target recognition itself, but signal production after the guanine-rich structure has formed.
Programmable nucleic acid sequences allow the recognition and signal-generating components to be designed around a selected target. This separates target recognition from the downstream G-quadruplex signal mechanism, giving the assay adaptable molecular architecture. In bioengineering, that flexibility supports development of different biosensors and nucleic acid assays without changing the central signal-generation principle.
G-quadruplex amplification can be implemented in isothermal formats, so signal generation does not rely exclusively on repeated temperature changes. This distinction is important for assay design because isothermal operation is compatible with portable and point-of-care technologies. The method therefore offers an alternative amplification strategy when simpler temperature requirements are desirable.
A typical assay links target recognition to the formation or production of a guanine-rich sequence, allows that sequence to generate a G-quadruplex structure, and then uses a ligand such as hemin to create a peroxidase-mimicking DNAzyme. The resulting catalytic activity produces a colorimetric or fluorescent readout that indicates target-associated amplification.
Researchers may choose G-quadruplex amplification when they need sensitive detection from small amounts of nucleic acid or other target material and want an alternative to conventional thermal cycling. Its compatibility with isothermal formats and programmable sequences makes it relevant to biosensors, pathogen detection, nucleic acid diagnostics, and molecular assays.
The catalytic G-quadruplex-hemin system can generate colorimetric or fluorescent outputs, allowing target-associated events to be monitored through different signal formats. In bioengineering, these outputs support sensitive biosensors, pathogen detection, nucleic acid diagnostics, and molecular assays. Isothermal compatibility also connects the approach with portable and point-of-care detection technologies.