The kinases male germ cell-associated kinase and cell cycle-related kinase regulate kinesin-2 motility in Caenorhabditis elegans neuronal cilia

Traffic. 2018 Jul;19(7):522-535. doi: 10.1111/tra.12572. Epub 2018 May 17.


Kinesin-2 motors power anterograde intraflagellar transport (IFT), a highly ordered process that assembles and maintains cilia. However, it remains elusive how kinesin-2 motors are regulated in vivo. Here, we performed forward genetic screens to isolate suppressors that rescue the ciliary defects of OSM-3-kinesin (homolog of mammalian homodimeric kinesin-2 KIF17) mutants in Caenorhabditis elegans. We identified the C. elegans dyf-5 and dyf-18, which encode the homologs of mammalian male germ cell-associated kinase and cell cycle-related kinase, respectively. Using time-lapse fluorescence microscopy, we show that DYF-5 and DYF-18 are IFT cargo molecules and are enriched at the distal segments of sensory cilia. Mutations of dyf-5 and dyf-18 generate elongated cilia and ectopic localization of the heterotrimeric kinesin-2 (kinesin-II) at the ciliary distal segments. Genetic analyses reveal that dyf-5 and dyf-18 are important for stabilizing the interaction between IFT particles and OSM-3-kinesin. Our data suggest that DYF-5 and DYF-18 act in the same pathway to promote handover between kinesin-II and OSM-3 in sensory cilia.

Keywords: CCRK; MAK; cilia; intraflagellar transport; kinesin-2.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans / metabolism
  • Caenorhabditis elegans Proteins / genetics
  • Caenorhabditis elegans Proteins / metabolism*
  • Cilia / metabolism
  • Kinesins / genetics
  • Kinesins / metabolism
  • Mitogen-Activated Protein Kinases / genetics
  • Mitogen-Activated Protein Kinases / metabolism*
  • Neurons / metabolism*
  • Protein Serine-Threonine Kinases / genetics
  • Protein Serine-Threonine Kinases / metabolism*
  • Protein Transport


  • Caenorhabditis elegans Proteins
  • OSM-3 protein, C elegans
  • DYF-18 protein, C elegans
  • Protein Serine-Threonine Kinases
  • DYF-5 protein, C elegans
  • Mitogen-Activated Protein Kinases
  • Kinesins