The behaviors and fates of cells are specified by the proteins they express and by the distribution of those proteins within the cell. One way that proteins are targeted to specific subcellular sites is via the localization of their corresponding mRNAs. Like other aspects of mRNA metabolism, localization is governed by specific RNA-protein recognition events. This proposal seeks to investigate the RNA-protein recognition events that mediate mRNA localization in Drosophila oocytes. It focuses on K10 mRNA, which is representative of a relatively large class of mRNAs (~30 members) that are synthesized in ovarian nurse cells and selectively transported into the oocyte during early stages of oogenesis. Previous studies have identified a small sequence element, called the TLS (transport/localization sequence), that is required and sufficient for K10 mRNA localization. The specific aims of the current proposal are: (1) To define precisely the structural features of the TLS that are required for its in vivo localization activity, (2) To determine whether the activity of the TLS is affected by its position in the mRNA, and (3) To identify and characterize proteins that bind the TLS.
