Small-molecule-catalysed deamination enables transcriptome-wide profiling of N⁶-methyladenosine in RNA

Area of Science:

• Biochemistry
• Organic Chemistry
• Molecular Biology

Background:

• Traditional deamination methods use harsh acidic conditions, limiting applications for biological molecules like DNA and RNA.
• Selective modification of nucleic acids is crucial for understanding gene regulation and epigenetic modifications.

Purpose of the Study:

• To develop a mild and selective deamination method compatible with DNA and RNA.
• To establish a novel sequencing technique for base-resolution detection of adenosine methylation.

Main Methods:

• Employing a cooperative catalysis system with a carbonyl organocatalyst and a Lewis acid.
• Utilizing an N-nitrosation strategy to form a carbon-nitro intermediate, followed by rearrangement to N-nitrosamine.
• Applying the method to deaminate adenine to hypoxanthine, while N6-methyladenosine remains intact.

Main Results:

• Selective deamination of unsubstituted DNA/RNA bases under mild conditions.
• Adenine was successfully deaminated to hypoxanthine, which is recognized as guanine by polymerases.
• N6-methyladenosine sites were resistant to deamination, preserving their adenine identity.

Conclusions:

• The developed N-nitrosation strategy offers a mild and effective approach for selective deamination of nucleic acids.
• This method enables a low-input, base-resolution sequencing technique for detecting adenosine methylation.
• Chemical cooperative catalysis-assisted N6-methyladenosine sequencing provides a new tool for epigenetics research.