G-quadruplex: Flexible conformational changes by cations, pH, crowding and its applications to biosensing.

Area of Science:

• Molecular Biology
• Biochemistry
• Structural Biology

Background:

• G-quadruplex (G4) structures are non-canonical formations in G-rich nucleic acid sequences.
• G4s are crucial for biological processes including telomere maintenance, transcription, and DNA replication.
• Typical G4 topologies include parallel, anti-parallel, and hybrid forms, stabilized by metal cations.

Purpose of the Study:

• To review recent studies on the impact of surrounding conditions on G4 conformations.
• To highlight the applications of G4s, particularly in biosensor development.
• To bridge the gap between experimental conditions and practical sample environments for G4 applications.

Main Methods:

• Literature review of recent research on G4 structures.
• Analysis of studies investigating G4 conformational changes under varying conditions (metal cations, pH, crowding).
• Examination of G4-based biosensor designs and performance.

Main Results:

• G4 conformations are highly sensitive to environmental factors such as metal cations, pH, and molecular crowding.
• These conformational changes influence the functionality and application potential of G4s.
• G4s serve as effective scaffolds for aptamers, leading to G4-aptamer based biosensors.

Conclusions:

• Understanding the influence of surrounding conditions is critical for the effective application of G4s.
• G4-based biosensors show promise, but challenges remain in matching experimental and real-world conditions.
• Further research is needed to optimize G4 stability and function in diverse biological environments.