Intrinsic control of muscle attachment sites matching
- French National Centre for Scientific Research, France
- Université de Toulouse, France
Abstract
Myogenesis is an evolutionarily conserved process. Little known, however, is how the morphology of each muscle is determined, such that movements relying upon contraction of many muscles are both precise and coordinated. Each Drosophila larval muscle is a single multinucleated fiber whose morphology reflects expression of distinctive identity Transcription Factors (iTFs). By deleting transcription cis-regulatory modules of one iTF, Collier, we generated viable muscle identity mutants, allowing live imaging and locomotion assays. We show that both selection of muscle attachment sites and muscle/muscle matching is intrinsic to muscle identity and requires transcriptional reprogramming of syncytial nuclei. Live-imaging shows that the staggered muscle pattern involves attraction to tendon cells and heterotypic muscle-muscle adhesion. Unbalance leads to formation of branched muscles, and this correlates with locomotor behavior deficit. Thus, engineering Drosophila muscle identity mutants allows to investigate, in vivo, physiological and mechanical properties of abnormal muscles.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
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Funding
Centre National de la Recherche Scientifique
- Alexandre Carayon
- Laetitia Bataillé
- Gaëlle Lebreton
- Laurence Dubois
- Aurore Pelletier
- Yannick Carrier
- Antoine Wystrach
- Alain Vincent
- Jean-Louis Frendo
Centre de Biologie Integrative de Toulouse (AOCBI2018)
- Jean-Louis Frendo
AFM-Téléthon (Research grant 21887)
- Alain Vincent
Agence Nationale de la Recherche (13-BSVE2-0010-01)
- Alain Vincent
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Carayon et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Intrinsic control of muscle attachment sites matching
eLife 9:e57547.
https://doi.org/10.7554/eLife.57547
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