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In Vitro Differentiation of Mature Myofibers for Live Imaging
Published on: January 7, 2017
Sarcomere formation in dystrophic skeletal muscle
Experimental Cell Biology
|January 1, 1981
Summary
Early sarcomere organization in chick embryos was studied. Dystrophic embryos showed delayed thick filament and polyribosome appearance, leading to unorganized sarcomeres.
Area of Science:
- Developmental Biology
- Muscle Biology
- Electron Microscopy
Background:
- Sarcomere organization is crucial for muscle function.
- Duchenne muscular dystrophy (DMD) is a severe genetic disorder affecting muscle.
- Chick embryos provide a model for studying early muscle development.
Purpose of the Study:
- To investigate early in vivo sarcomere organization in normal and dystrophic chick embryos.
- To identify developmental differences in myotomal cells during early muscle formation.
Main Methods:
- Brachial somites (17-22) were collected from chick embryos (stages 16-28).
- Samples were processed for electron microscopy.
- Normal and dystrophic embryonic tissues were compared.
Main Results:
- Thick filament assembly was delayed in dystrophic myotomal cells.
- Delayed appearance of long polyribosomes was observed in dystrophic cells.
- By stage 28, dystrophic sarcomeres were unorganized with poor myofilament alignment and underdeveloped periodic tubules.
Conclusions:
- Dystrophic conditions disrupt early sarcomere organization.
- Delays in filament assembly and polyribosome formation contribute to abnormal muscle development.
- These findings highlight critical early events in muscle development affected by dystrophy.
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Each myosin...
Each myosin...