Tension-driven multi-scale self-organisation in human iPSC-derived muscle fibers
Abstract
Human muscle is a hierarchically organised tissue with its contractile cells called myofibers packed into large myofiber bundles. Each myofiber contains periodic myofibrils built by hundreds of contractile sarcomeres that generate large mechanical forces. To better understand the mechanisms that coordinate human muscle morphogenesis from tissue to molecular scales, we adopted a simple in vitro system using induced pluripotent stem cell-derived human myogenic precursors. When grown on an unrestricted two-dimensional substrate, developing myofibers spontaneously align and self-organise into higher-order myofiber bundles, which grow and consolidate to stable sizes. Following a transcriptional boost of sarcomeric components, myofibrils assemble into chains of periodic sarcomeres that emerge across the entire myofiber. More efficient myofiber bundling accelerates the speed of sarcomerogenesis suggesting that tension generated by bundling promotes sarcomerogenesis. We tested this hypothesis by directly probing tension and found that tension build-up precedes sarcomere assembly and increases within each assembling myofibril. Furthermore, we found that myofiber ends stably attach to other myofibers using integrin-based attachments and thus myofiber bundling coincides with stable myofiber bundle attachment in vitro. A failure in stable myofiber attachment results in a collapse of the myofibrils. Overall, our results strongly suggest that mechanical tension across sarcomeric components as well as between differentiating myofibers is key to coordinate the multi-scale self-organisation of muscle morphogenesis.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting file; Source Data files have been provided for all Figures; Table S1 contains the analysis of the sequencing data shown in Figure 3
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GSE164874_SecondaryDifferentiation_raw_counts.xlsxNCBI Gene Expression Omnibus, GSE164874.
Article and author information
Author details
Funding
Human Frontier Science Program (RGP0052/2018)
- Frank Schnorrer
Agence Nationale de la Recherche (ANR-18-CE45-0016-01 MITO-DYNAMICS)
- Bianca H Habermann
Agence Nationale de la Recherche (Agence Nationale de la Recherche (ANR))
- Fabio Marchiano
Agence Nationale de la Recherche (ANR-10-INBS-04-01)
- Pierre-François Lenne
Agence Nationale de la Recherche (ANR-16-CONV-0001)
- Frank Schnorrer
Aix-Marseille Université (ANR-16-CONV-0001)
- Frank Schnorrer
Turing Centre for Living Systems (ANR-16-CONV-0001)
- Frank Schnorrer
Eunice Kennedy Shriver National Institute of Child Health and Human Development (F31HD100033)
- Margarete Díaz-Cuadros
la Caixa" Foundation " (LCF/BQ/AA18/11680032)
- Alejandra Rodríguez-delaRosa
Human Frontier Science Program (RGP0052/2018)
- Olivier Pourquié
Centre National de la Recherche Scientifique
- Frank Schnorrer
Centre National de la Recherche Scientifique
- Pierre-François Lenne
Centre National de la Recherche Scientifique
- Bianca H Habermann
European Research Council (ERC-2019-SyG 856118)
- Frank Schnorrer
Aix-Marseille Université (ANR-11-IDEX-0001-02)
- Frank Schnorrer
Agence Nationale de la Recherche (MUSCLE-FORCES)
- Frank Schnorrer
Agence Nationale de la Recherche (ANR-18-CE45-0016-01 MITO-DYNAMICS)
- Frank Schnorrer
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Mao 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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