Determine base-resolved positions of ac4C modifications in mRNA

Determine the precise nucleotide positions of N4-acetylcytidine (ac4C) modifications in mRNA transcripts, given that current acRIP-seq approaches provide only relative peak positions rather than base-resolved sites.

Background

AcRIP-seq is widely used to identify mRNA regions enriched for ac4C but does not provide single-nucleotide resolution, leaving only relative peak positions available. This limitation prevents unambiguous assignment of the modified cytidine within the peak region and hinders mechanistic studies of ac4C deposition and recognition by NAT10 and other RNA-binding factors.

The paper emphasizes that unlike DNA 6mA methylation, for which individual modified bases can often be pinpointed, base-resolved ac4C positions in mRNA remain unlocalized with current data, motivating the need for methods or analyses that achieve nucleotide precision.