In PLoS Genetics this week, an international team of researchers report that nucleolin is required for DNA methylation and the expression of rRNA gene variants in Arabidopsis thaliana. In plants with a disrupted nucleolin-like protein gene, AtNUC-L1, transcription of rRNA variants is repressed, and the most highly represented rRNA gene variant, inactive in wild-type plants, is reactivated in AtNUC-L1 mutants, the researchers write.