Abstract

Asymmetric RNA localization is required for many developmental processes in a wide range of organisms. For example, wingless and pair‐rule transcripts are localized to the apical membrane of polarized cells. It has been unclear, however, if this localization is important for biological activity and, in addition, how the transcripts are transported. Two recent studies(1,2) have identified cis‐elements and trans‐acting factors that are required for the asymmetric localization of mRNAs. Correct localization is shown to be required for biological activity, and a mechanism of RNA transport involving the microtubule motor dynein has been revealed. BioEssays 23:869–872, 2001. © 2001 John Wiley & Sons, Inc.