Journal of Genetics

, Volume 93, Issue 2, pp 379–388 | Cite as

Roles of the troponin isoforms during indirect flight muscle development in Drosophila



Troponin proteins in cooperative interaction with tropomyosin are responsible for controlling the contraction of the striated muscles in response to changes in the intracellular calcium concentration. Contractility of the muscle is determined by the constituent protein isoforms, and the isoforms can switch over from one form to another depending on physiological demands and pathological conditions. In Drosophila, a majority of the myofibrillar proteins in the indirect flight muscles (IFMs) undergo post-transcriptional and post-translational isoform changes during pupal to adult metamorphosis to meet the high energy and mechanical demands of flight. Using a newly generated Gal4 strain (UH3-Gal4) which is expressed exclusively in the IFMs, during later stages of development, we have looked at the developmental and functional importance of each of the troponin subunits (troponin-I, troponin-T and troponin-C) and their isoforms. We show that all the troponin subunits are required for normal myofibril assembly and flight, except for the troponin-C isoform 1 (TnC1). Moreover, rescue experiments conducted with troponin-I embryonic isoform in the IFMs, where flies were rendered flightless, show developmental and functional differences of TnI isoforms and importance of maintaining the right isoform.


troponin isoforms myofibril flight muscle Drosophila



We thank our laboratory members for their critical comments. This work was supported by financial assistance from Department of Biotechnology, Department of Science and Technology, Government of India, New Delhi and Indian Institute of Science, Bangalore.


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Copyright information

© Indian Academy of Sciences 2014

Authors and Affiliations

  1. 1.Molecular Reproduction, Development and GeneticsIndian Institute of ScienceBangaloreIndia
  2. 2.Department of Studies in ZoologyUniversity of MysoreMysoreIndia

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