The localization of RNAs to specific areas within cells or embryos is essential for many aspects of development. Generally, RNA localization acts by facilitating localized protein production. However, Kloc and co-workers now report that both coding and non-coding RNAs help to organize the cytoskeleton in the vegetal cortex of Xenopus oocytes (see ). By using antisense oligonucleotides to deplete oocytes of VegT mRNA or non-coding Xlsirts RNA, the researchers show that the destruction of these RNAs, which normally localize to the vegetal cortex, disrupts the cytokeratin (but not the actin) cytoskeleton at the vegetal cortex in a transcript-specific manner, and interferes with germinal granule structure and with primordial germ cell formation. The researchers also show that VegT and Xlsirts RNAs integrate into the cytokeratin cytoskeleton in Xenopus oocytes, and suggest that RNAs may play similar structural roles in other cell types and organisms.
