Conversion of anterograde into retrograde trains is an intrinsic property of intraflagellar transport

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Adrian Pascal Nievergelt - , Max Planck Institute of Molecular Cell Biology and Genetics (Author)
  • Ilia Zykov - , Max Planck Institute of Molecular Cell Biology and Genetics (Author)
  • Dennis Diener - , Max Planck Institute of Molecular Cell Biology and Genetics (Author)
  • Aditya Chhatre - , Chair of BioNano-Tools, Clusters of Excellence PoL: Physics of Life, Max Planck Institute of Molecular Cell Biology and Genetics (Author)
  • Tim Oliver Buchholz - , Max Planck Institute of Molecular Cell Biology and Genetics, Center for Systems Biology Dresden (CSBD) (Author)
  • Markus Delling - , University of California at San Francisco (Author)
  • Stefan Diez - , Chair of BioNano-Tools, Clusters of Excellence PoL: Physics of Life, Max Planck Institute of Molecular Cell Biology and Genetics (Author)
  • Florian Jug - , Max Planck Institute of Molecular Cell Biology and Genetics, Center for Systems Biology Dresden (CSBD), Human Technopole (Author)
  • Luděk Štěpánek - , Max Planck Institute of Molecular Cell Biology and Genetics, Czech Academy of Sciences (Author)
  • Gaia Pigino - , Max Planck Institute of Molecular Cell Biology and Genetics, Human Technopole (Author)

Abstract

Cilia or eukaryotic flagella are microtubule-based organelles found across the eukaryotic tree of life. Their very high aspect ratio and crowded interior are unfavorable to diffusive transport of most components required for their assembly and maintenance. Instead, a system of intraflagellar transport (IFT) trains moves cargo rapidly up and down the cilium (Figure 1A).1–3 Anterograde IFT, from the cell body to the ciliary tip, is driven by kinesin-II motors, whereas retrograde IFT is powered by cytoplasmic dynein-1b motors.4 Both motors are associated with long chains of IFT protein complexes, known as IFT trains, and their cargoes.5–8 The conversion from anterograde to retrograde motility at the ciliary tip involves (1) the dissociation of kinesin motors from trains,9 (2) a fundamental restructuring of the train from the anterograde to the retrograde architecture,8,10,11 (3) the unloading and reloading of cargo,2 and (4) the activation of the dynein motors.8,12 A prominent hypothesis is that there is dedicated calcium-dependent protein-based machinery at the ciliary tip to mediate these processes.4,13 However, the mechanisms of IFT turnaround have remained elusive. In this study, we use mechanical and chemical methods to block IFT at intermediate positions along the cilia of the green algae Chlamydomonas reinhardtii, in normal and calcium-depleted conditions. We show that IFT turnaround, kinesin dissociation, and dynein-1b activation can consistently be induced at arbitrary distances from the ciliary tip, with no stationary tip machinery being required. Instead, we demonstrate that the anterograde-to-retrograde conversion is a calcium-independent intrinsic ability of IFT.

Details

Original languageEnglish
Pages (from-to)4071-4078.e4
JournalCurrent biology
Volume32
Issue number18
Early online date3 Aug 2022
Publication statusPublished - 26 Sept 2022
Peer-reviewedYes

External IDs

Mendeley fa51a9ad-607f-33ee-95cf-51ab081d3a00
PubMed 35926510
ORCID /0000-0002-0750-8515/work/142235550

Keywords

Research priority areas of TU Dresden

Keywords

  • cilia and flagella, ciliary tip, intraflagellar transport, micromanipulator, TIRF microscopy, total-internal reflection microscopy, Cilia/metabolism, Calcium/metabolism, Kinesins, Cytoplasmic Dyneins/metabolism, Biological Transport, Dyneins/metabolism, Flagella/physiology