Cilia are microtubule-based appendages that project from the surfaces of various eukaryotic cells and play critical roles in sensing extracellular stimuli and transducing developmental signals. Defects in the assembly and functions of cilia result in a variety of congenital disorders, which are collectively called the ciliopathies.
The bidirectional trafficking of ciliary proteins along the microtubule-based axoneme is mediated by the intraflagellar transport (IFT) machinery, which contains the two large multisubunit complexes IFT-A and IFT-B. Anterograde protein trafficking from the base to the tip of cilia is mediated by the IFT-B complex driven by kinesin-2 motor proteins, whereas retrograde trafficking is mediated by the IFT-A complex driven by the dynein-2 complex.
I will introduce the architecture and function of IFT machinery revealed by utilizing the visible immunoprecipitation (VIP) assay, which we recently developed as a simple and flexible strategy for visually detecting protein-protein interactions, and CRISPR/Cas9 genome editing.