IFT-Cargo Interactions and Protein Transport in Cilia

Trends Biochem Sci. 2015 Dec;40(12):765-778. doi: 10.1016/j.tibs.2015.09.003. Epub 2015 Oct 21.


The motile and sensory functions of cilia and flagella are indispensable for human health. Cilia assembly requires a dedicated protein shuttle, intraflagellar transport (IFT), a bidirectional motility of multi-megadalton protein arrays along ciliary microtubules. IFT functions as a protein carrier delivering hundreds of distinct proteins into growing cilia. IFT-based protein import and export continue in fully grown cilia and are required for ciliary maintenance and sensing. Large ciliary building blocks might depend on IFT to move through the transition zone, which functions as a ciliary gate. Smaller, freely diffusing proteins, such as tubulin, depend on IFT to be concentrated or removed from cilia. As I discuss here, recent work provides insights into how IFT interacts with its cargoes and how the transport is regulated.

Keywords: diffusion; dynein; flagella; intraflagellar transport; kinesin-2; microtubule; tubulin.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Animals
  • Cilia / chemistry
  • Cilia / metabolism*
  • Humans
  • Microtubules / chemistry
  • Microtubules / metabolism
  • Protein Transport
  • Proteins / chemistry
  • Proteins / metabolism*


  • Proteins