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For decades it has been established that head muscle development differs from trunk muscle development. Similarly known, even though not in such detail, is that different subgroups of head muscles develop dependent on different underlying gene regulatory networks. Even less well studied are the tissue interactions during the developmental processes. Muscles derived from pharyngeal arch mesoderm depend on interactions with endoderm and neural crest cells, and, to a minor extent, ectodermal cues. Extraocular eye muscles respond to a mix of signals from surrounding mesoderm, but also neural crest cells; however, they are independent of endodermal cues. Head muscles derived from occipital paraxial mesoderm depend on tissue interactions similar to pharyngeal arch muscles but have a different migration trajectory. While the pharyngeal arch mesodermal cells and neural crest cells largely migrate from dorsal to ventral, the occipital paraxial mesodermal cells migrate from dorsal to ventral and from posterior to anterior. During the migration these cells proliferate and even start to differentiate, while pharyngeal mesodermal cells begin the differentiation process after reaching their respective pharyngeal arches. Here we present an overview of tissue interactions during the development of different head muscle populations, highlighting general concepts and main differences. Topic Category: Neural Crest, Placodes and Craniofacial Development Keywords: Craniofacial muscles, Myogenesis Funding or Support Information: NSF #2000005 to JMZC
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Anterior trunk muscle shows mix of axial and appendicular developmental patterns
Background: Skeletal muscle in the trunk derives from the somites, paired segments of paraxial mesoderm. Whereas axial musculature develops within the somite, appendicular muscle develops following migration of muscle precursors into lateral plate mesoderm. The development of muscles bridging axial and appendicular systems appears mixed. Results: We examine development of three migratory muscle precursor-derived muscles in zebrafish: the sternohyoideus (SH), pectoral fin (PF), and posterior hypaxial (PHM) muscles. We show there is an anterior to posterior gradient to the developmental gene expression and maturation of these three muscles. SH muscle precursors exhibit a long delay between migration and differentiation, PF muscle precursors exhibit a moderate delay in differentiation, and PHM muscle precursors show virtually no delay between migration and differentiation. Using lineage tracing, we show that lateral plate contribution to the PHM muscle is minor, unlike its known extensive contribution to the PF muscle and absence in the ventral extension of axial musculature. Conclusions: We propose that PHM development is intermediate between a migratory muscle mode and an axial muscle mode of development, wherein the PHM differentiates after a very short migration of its precursors and becomes more anterior primarily by elongation of differentiated muscle fibers.
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- Award ID(s):
- 1828327
- PAR ID:
- 10217564
- Date Published:
- Journal Name:
- Developmental dynamics
- Volume:
- 248
- Issue:
- 10
- ISSN:
- 1097-0177
- Page Range / eLocation ID:
- 961-968
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/dvdy.95
