Effects of Tropomyosin Deficiency in Flight Muscle of Drosophila Melanogaster

  • Justin Molloy
  • Andrew Kreuz
  • Rehae Miller
  • Terese Tansey
  • David Maughan
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 332)


We have studied the structure and function of muscle fibers in which tropomyosin stoichiometry has been reduced by genetic mutation. We used a Drosophila melanogaster flightless mutant Ifm(3)3 and a genetic cross of this mutant with wild type flies to achieve a gradation of tropomyosin gene dosage. We measured the flight ability and wingbeat frequency of the live insects and the ultrastructure and mechanochemistry of isolated single flight muscle fibers.

Flight ability is impaired when tropomyosin gene dosage is reduced. Wingbeat frequency also depends upon gene dosage as well as the severity of myofilament lattice disruption and the number of myofilaments in the organized core of the myofibrils. A reduction in number of myofilaments appears to result in a reduction in active muscle stiffness without resulting in an appreciable change in kinetics of force production.

Ifm(3)3 is trapped in a relaxed state and cannot generate active force. However, tight-binding rigor cross-bridges are able to form; in the absence of ATP, Ifm(3)3 muscle fibers have high stiffness and force.


Sarcomere Length Flight Muscle Indirect Flight Muscle Flight Ability Wing Beat Frequency 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Mogami, K. & Hotta, Y. Mol. Gen. Genet. 183, 409–417 (1981).PubMedCrossRefGoogle Scholar
  2. 2.
    Sparrow, J., Drummond, D. Peckham, M. Hennessey, E. & White, D. J. Cell Sci. 14 73–78 (1991.)Google Scholar
  3. 3.
    Karlik, C.C. & Fyrberg, E.A. Cell 41, 57–66 (1985).PubMedCrossRefGoogle Scholar
  4. 4.
    Unwin, D.M. & Ellington, C. P. J. Exp. Biol. 82, 377–378 (1979).Google Scholar
  5. 5.
    Tansey, T., Schultz, J., Miller R., & Storti, R. Mol. Cell Biol (1991), in press.Google Scholar
  6. 6.
    Basi, G.S. & Storti, R.V. J. Biol. Chem. 261, 819–827 (1986).Google Scholar
  7. 7.
    Karlik, C.C. & Fyrberg, E.A. Mol. Cell Biol. 6, 1965–1973 (1986).PubMedGoogle Scholar
  8. 8.
    Kawai, M. & Brandt, P.W. J. Muscle Res. Cell Motility 1, 279–303 (1980).CrossRefGoogle Scholar
  9. 9.
    Thorson, J. & White, D.C.S. J. Physiol. (Lond.) 343, 59–84, (1983).Google Scholar
  10. 10.
    Wray, J. Nature 280, 325–326 (1979).CrossRefGoogle Scholar
  11. 11.
    Pringle, J.W.S. Insect Flight. Cambridge, Cambridge Univ. Press. (1957).Google Scholar
  12. 12.
    Ellington, C.P. J. Exp. Biol. 115, 293–304 (1985).PubMedGoogle Scholar
  13. 13.
    Tansey, T., Mikus, M.D. Dumoulin, M. & Storti, R.V. EMBO J. 6 1375–1383.Google Scholar
  14. 14.
    Sheppard, D.E. Drosph. Inf. Serv. 51, 150 (1974).Google Scholar

Copyright information

© Springer Science+Business Media New York 1993

Authors and Affiliations

  • Justin Molloy
    • 1
  • Andrew Kreuz
    • 2
  • Rehae Miller
    • 3
  • Terese Tansey
    • 3
  • David Maughan
    • 4
  1. 1.Department of BiologyUniversity of YorkHeslingtonUK
  2. 2.Department of Molecular GeneticsOhio State UniversityColumbusUSA
  3. 3.Department of BiologyGeorgetown UniversityWashington DCUSA
  4. 4.Department of Physiology and BiophysicsUniversity of VermontBurlingtonUSA

Personalised recommendations