Pulse-chase experiments reveal dynamics of RNA binding protein Exuperantia inDrosophila melanogaster eggchambers

AbstractIn cells, mRNA can be associated with various proteins, forming ribonucleoprotein complexes (RNPs) which take part in spatiotemporal control of translation. In theDrosophila melanogasterdeveloping egg chamber, a set of RNPs is transported from the nurse cells to the oocyte and targeted selectively to specific cellular locations. This mRNA sorting process leads to the final oocyte polarization pre-defining the body axes of the future embryo. However, how mRNA is encoded for selection and directed transport is mechanistically not well understood. A master mRNA involved in body axes formation isbicoid, which localizes anterolaterally and is essential for head and thorax definition of the embryo. A protein that was identified essential forbicoidanterior localization is Exuperantia (Exu). Here, we use a live imaging–based pulse-chase approach, which reveals selective transport dynamics of Exu from nurse cells to the oocyte during mid to late-stage oogenesis.