Since mRNA localization is a dynamic process, we are using live imaging of different components of the mRNA localization machinery to determine how these complexes are assembled, transported, and anchored in vivo. We are particularly interested in identifying subunits that alter the trafficking behavior of particular RNPs and redirect them to novel locations. We have recently identified such a subunit and we are characterizing its mode of action using live imaging of GFP tagged complexes in the Drosophila egg chamber.