Intraflagellar transport particles participate directly in cilium-generated signaling in Chlamydomonas

Cell. 2006 May 5;125(3):549-62. doi: 10.1016/j.cell.2006.02.044.

Abstract

Primary cilia are widely used for signal transduction during development and in homeostasis and are assembled and maintained by intraflagellar transport (IFT). Here, we have dissected the role of IFT in signaling within the flagella (structural and functional counterparts of cilia) of the biflagellated green alga Chlamydomonas. Using a conditional IFT mutant enables us to deplete the IFT machinery from intact, existing flagella. We identify a cGMP-dependent protein kinase (CrPKG) within flagella as the substrate of a protein tyrosine kinase activated by flagellar adhesion during fertilization. We demonstrate that flagellar adhesion stimulates association of CrPKG with a new flagellar compartment. Moreover, formation of the compartment requires IFT, and IFT particles themselves are part of the compartment. Our results lead to a model in which the IFT machinery is required not only for assembling cilia and flagella but also for organizing a signaling pathway within the organelles during cilium-generated signaling.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cell Adhesion / physiology
  • Cell Compartmentation / physiology
  • Cell Movement / physiology
  • Chlamydomonas reinhardtii / metabolism*
  • Chlamydomonas reinhardtii / ultrastructure
  • Cilia / metabolism*
  • Cilia / ultrastructure
  • Cyclic GMP-Dependent Protein Kinases / genetics
  • Cyclic GMP-Dependent Protein Kinases / isolation & purification
  • Cyclic GMP-Dependent Protein Kinases / metabolism*
  • Cytoplasm / metabolism
  • DNA, Complementary / analysis
  • DNA, Complementary / genetics
  • Fertilization / physiology
  • Flagella / metabolism*
  • Flagella / ultrastructure
  • Molecular Sequence Data
  • Mutation / physiology
  • Phosphorylation
  • Protein Transport / physiology
  • Protozoan Proteins / genetics
  • Protozoan Proteins / isolation & purification
  • Protozoan Proteins / metabolism*
  • Signal Transduction / physiology
  • Tyrosine / chemistry
  • Tyrosine / metabolism

Substances

  • DNA, Complementary
  • Protozoan Proteins
  • Tyrosine
  • Cyclic GMP-Dependent Protein Kinases

Associated data

  • GENBANK/AAT81143
  • GENBANK/AY605666