Intraflagellar transport (IFT) is essential for the assembly and maintenance of eukaryotic flagella and cilia and is a fundamental characteristic of almost all eukaryotic cells. IFT is characterized by the movement of large protein complexes from the basal body to the flagellar tip by the microtubule-based motor protein kinesin II and from the tip back to the basal body by cytoplasmic dynein 1b. The IFT particles are not membrane bound, and the mechanism by which these particles interact with motor proteins and cargo are unknown. In order to begin understanding these interactions, IFT will be reconstituted in vitro using purified motor proteins and cargo polypeptides. Related experiments will focus on the binding of motor proteins to cargo polypeptides and the assembly of these multi-component IFT complexes. Additional experiments using temperature-sensitive mutants for the retrograde motor involved in IFT will focus on IFT as a component of a signal transduction system that negatively controls expression of flagellar genes. The PI will integrate the research project with undergraduate courses in cell biology. Moreover, the project will provide research training for undergraduate and graduate students.
