Guide RNA acrobatics: the one-for-two shuffle.

RNA modifications are crucial for the proper function of the RNAs. The sites of pseudouridines are often specified by dual hairpin guide RNAs, with one or both hairpins identifying a target uridine. In this issue of Genes & Development, Jády and colleagues (pp. 70-83) identify a novel mechanism by which a single guide RNA hairpin can specify two uridines adjacent to each other or separated by 1 nt; i.e., one for two or guide RNA acrobatics.