Development of a Fluorescent Probe for Specific Visualization of Intracellular DNA i-Motif Participating in Key...

Area of Science:

• Molecular Biology
• Biochemistry
• Chemical Biology

Background:

• The i-motif DNA structure is increasingly recognized for its biological significance.
• Studying intracellular i-motif is challenging due to the lack of efficient visualization methods.

Purpose of the Study:

• To develop a novel fluorescent probe for specific intracellular i-motif detection.
• To investigate the biological function of i-motif in cellular processes.

Main Methods:

• Synthesis of a coumarin-carbazole-based fluorescent probe (IMCC-6).
• Application of IMCC-6 for visualizing i-motif in live cells and zebrafish.
• Colocalization studies of i-motif with rDNA and RNA polymerase I.

Main Results:

• IMCC-6 demonstrated high selectivity and recognition ability for i-motif.
• Successfully visualized ribosome DNA (rDNA) i-motif within nucleoli.
• Observed colocalization of rDNA i-motif with RNA polymerase I, suggesting a regulatory role in transcription.

Conclusions:

• IMCC-6 is the first small-molecule fluorescent probe for specific in-cell and in vivo i-motif visualization.
• Provides direct evidence for i-motif's involvement in key biological functions.
• Highlights the potential regulatory role of rDNA i-motif in rDNA transcription.