The 3' untranslated region (3' UTR) can control gene expression by affecting the localization, stability and translation of mRNAs. The recent finding that 3' UTRs can control the decapping rate of mRNAs, in combination with their ability to influence the initiation of translation, suggests that 3' UTRs act through a direct or indirect interaction between the 3' and 5' ends of mRNAs.