Development of an RNA–protein crosslinker to capture protein interactions with diverse RNA structures in cells

Characterization of RNA–protein interaction is fundamental for understanding the metabolism and function of RNA. UV crosslinking has been widely used to map the targets of RNA-binding proteins, but is limited by low efficiency, requirement for zero-distance contact, and biases for single-stranded RNA structure and certain residues of RNA and protein. Here, we report the development of an RNA–protein crosslinker (AMT–NHS) composed of a psoralen derivative and an N -hydroxysuccinimide ester group, which react with RNA bases and primary amines of protein, respectively. We show that AMT–NHS can penetrate into living yeast cells and crosslink Cbf5 to H/ACA snoRNAs with high specificity. The crosslinker induced different crosslinking patterns than UV and targeted both single- and double-stranded regions of RNA. The crosslinker provides a new tool to capture diverse RNA–protein interactions in cells.