Advances in i-motif structures: Stability, gene expression, and therapeutic applications.

Area of Science:

• Biochemistry and Molecular Biology
• Genetics
• Nanotechnology

Background:

• The i-motif is a unique DNA secondary structure formed by cytosine-rich sequences under acidic conditions.
• It is implicated in the regulation of gene expression, particularly in the promoter regions of key oncogenes (e.g., Bcl-2, C-MYC, KRAS).
• Its pH-sensitive nature presents opportunities for targeted therapies and diagnostic tools.

Purpose of the Study:

• To review the multifaceted roles of i-motifs in biological processes.
• To explore the therapeutic potential of i-motifs in various diseases, including oncology, metabolic disorders, and neurodegenerative conditions.
• To highlight recent advances and future directions in i-motif-based nanotechnology and precision medicine.

Main Methods:

• Literature review of studies on i-motif structure, function, and applications.
• Analysis of i-motif interactions with transcription factors and ligands.
• Examination of i-motif-based nanotechnology, including pH sensors and drug delivery systems.

Main Results:

• i-motifs dynamically regulate oncogene activity through interactions with transcription factors.
• pH-sensitive i-motif structures enable development of cellular pH sensors ('i-switch') and targeted drug delivery systems (DNA hydrogels).
• Challenges exist in developing specific i-motif ligands and detection methodologies.

Conclusions:

• i-motifs are crucial therapeutic targets and versatile tools with significant potential in precision medicine.
• Further research is needed to overcome current challenges and fully harness i-motif applications.
• i-motif-based strategies show promise for treating a range of diseases by leveraging their unique pH-dependent properties.