During oocyte development in Drosophila, intricate and orchestrated cellular rearrangements set up a functionally and physically polarized mature egg. Polesello et al. examined the role of the protein Dmoesin, whose homologs (ezrin, radixin, and moesin) in other organisms mediate interactions between the actin cytoskeleton and plasma membrane proteins. In oocytes, Dmoesin and actin coordinate to bring about the positioning of the posterior polarity determinant Oskar. Mutation of a conserved threonine residue suggests that phosphorylation of Dmoesin is important in organizing the cytoskeleton and in promoting the correct localization of posterior determinants. In Drosophila expressing mutant Dmoesin, anchorage of filamentous actin to the oocyte cortex was disrupted, resulting in aberrant anterior-posterior polarity in the future embryos. -- SMH
Nature Cell Biol. 4, 782 (2002).
