Yuan W Tian, Matthias Soller
In this issue of Molecular Cell, Meng et al. identify a reader for pseudouridine (Ψ) in mRNA. Ψ increases binding of SMD2, a member of the SM protein ring surrounding spliceosomal U1 and U2 snRNAs, and alters alternative splicing, revealing a new epitranscriptomic mechanism linked to splicing dysregulation in cancer through SMD2 overexpression.