Intraflagellar transport trains and motors: Insights from structure

Semin Cell Dev Biol. 2020 Nov:107:82-90. doi: 10.1016/j.semcdb.2020.05.021. Epub 2020 Jul 16.

Abstract

Intraflagellar transport (IFT) sculpts the proteome of cilia and flagella; the antenna-like organelles found on the surface of virtually all human cell types. By delivering proteins to the growing ciliary tip, recycling turnover products, and selectively transporting signalling molecules, IFT has critical roles in cilia biogenesis, quality control, and signal transduction. IFT involves long polymeric arrays, termed IFT trains, which move to and from the ciliary tip under the power of the microtubule-based motor proteins kinesin-II and dynein-2. Recent top-down and bottom-up structural biology approaches are converging on the molecular architecture of the IFT train machinery. Here we review these studies, with a focus on how kinesin-II and dynein-2 assemble, attach to IFT trains, and undergo precise regulation to mediate bidirectional transport.

Keywords: Cilia; Dynein; Intraflagellar transport; Kinesin; Microtubule; Motor protein.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Biological Transport
  • Flagella / metabolism*
  • Humans
  • Microtubules / metabolism
  • Models, Biological
  • Molecular Motor Proteins / metabolism*

Substances

  • Molecular Motor Proteins