Peter A. Takizawa
A Molecular and Cellular Analysis of How Cells Localize mRNAs and ProteinsCells, from bacteria to neurons, localize proteins to specific regions of their cytoplasm and plasma membrane. One means of localizing a specific protein within a cell is by transporting its mRNA to a defined region in the cytoplasm while regulating the translation of the mRNA. mRNA localization has been observed in many cell types including yeast, epithelial cells, and neurons. In yeast, the localization of ASH1 mRNA to the bud tip generates differences in cell fate between mother and daughter cells. In neurons, several mRNAs encoding proteins with roles in regulating synaptic strength have been found in the dendrites.
We employ a combination of biochemical and cellular analysis to understand the processes of mRNA and protein localization in both yeast and neurons. Proteins involved in the transport, anchoring and translational regulation of localized mRNAs are identified by affinity purification of specific mRNAs from cell extracts. Biochemical and higher order structural analysis are used to determine how localized mRNAs are recognized and assembled into ribonucleoprotein complexes. Fluorescence-based assays are employed to measure the transport and translational regulation of specific mRNAs in living cells.