Published October 17, 2025 | Version v1
Journal article

Nuclear 2′-O-methylation regulates RNA splicing through its binding protein FUBP1

  • 1. University of Chicago
  • 2. The Hong Kong University of Science and Technology

Description

2′-O-methylation (Nm) is an abundant RNA modification exists on different mammalian RNA species. However, potential Nm recognition by proteins has not been extensively explored. Here, we used RNA affinity purification, followed by mass spectrometry to identify Nm-binding proteins. The Nm-binding protein candidates exhibit enriched binding at known Nm sites. Some candidates display nuclear localization and functions. We focused on the splicing factor FUBP1. Electrophoretic mobility shift assay validated preference of FUBP1 to Nm-modified RNA. As FUBP1 predominantly binds intronic regions, we profiled Nm sites in chromatin-associated RNA (caRNA) and found Nm enrichment within introns. Depletion of Nm led to skipped exons, suggesting Nm-dependent splicing regulation. The caRNA Nm sites overlap with FUBP1-binding sites, and N m depletion reduced FUBP1 occupancy on modified regions. Furthermore, FUBP1 depletion induced exon skipping in Nm-modified genes, supporting its role in mediating Nm-dependent splicing regulation. Overall, our findings identify FUBP1 as an Nm-binding protein and uncover previously unrecognized nuclear functions for RNA Nm modification.

Data availability

All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. The sequencing data are accessible in the Gene Expression Omnibus through accession numbers GSE294792, GSE294793, and GSE294794. Published Nm-mut-seq dataset of internal mRNA (GSE174518); ENCODE datasets of eCLIP experiments targeting FUBP3 (ENCSR486YGP), IGF2BP1 (ENCSR744GEU), and IGF2BP3 (ENCSR993OLA); and their IgG control (GSE77629) were used for analysis.

Additional details

Identifiers

DOI
10.1126/sciadv.ady3894
Other
oai:uchicago.tind.io:16400

Funding

National Institutes of Health
RM1 HG008935
National Institutes of Health
R01 HL155909
Howard Hughes Medical Institute

UChicago Information

Division(s)
Biological Sciences Division, Physical Sciences Division
Department(s)
Chemistry, Molecular Genetics and Cell Biology