Calcium control of waveform in isolated flagellar axonemes of Chlamydomonas

J Cell Biol. 1980 Aug;86(2):446-55. doi: 10.1083/jcb.86.2.446.


The effect of Ca(++) on the waveform of reactivated, isolated axonemes of chlamydomonas flagella was investigated. Flagella were detached and isolated by the dibucaine procedure and demembranated by treatment with the detergent Nonidet; the resulting axomenes lack the flagellar membrane and basal bodies. In Ca(++)-buffered reactivation solutions containing 10(-6) M or less free Ca(++), the axonemes beat with a highly asymmetrical, predominantly planar waveform that closely resembled that of in situ flagella of forward swimming cells. In solutions containing 10(-4) M Ca(++), the axonemes beat with a symmetrical waveform that was very similar to that of in situ flagella during backward swimming. In 10(-5) M Ca(++), the axonemes were predominantly quiescent, a state that appears to be closely associated with changes in axomenal waveform or direction of beat in many organisms. Experiments in which the concentrations of free Ca(++), not CaATP(--) complex were independently varied suggested that free Ca(++), not CaATP(--), was responsible for the observed changes. Analysis of the flagellar ATPases associated with the isolated axonemes and the nonidet- soluble membrane-matrix fraction obtained during preparation of the axonemes showed that the axonemes lacked the 3.0S Ca(++)-activated ATPase, almost all of which was recovered in the membrane-matrix fraction. These results indicate that free Ca(++) binds directly to an axonemal component to alter flagellar waveform, and that neither the 3.0S CaATPase nor the basal bodies are directly involved in this change.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenosine Triphosphatases / metabolism
  • Calcium / pharmacology*
  • Cell Membrane / physiology
  • Cell-Free System
  • Chlamydomonas / physiology
  • Chlamydomonas / ultrastructure*
  • Dyneins / metabolism
  • Flagella / drug effects*
  • Flagella / enzymology
  • Flagella / physiology
  • Microtubules / physiology*
  • Movement


  • Adenosine Triphosphatases
  • Dyneins
  • Calcium