PUBLICATION
Myocyte Dedifferentiation Drives Extraocular Muscle Regeneration in Adult Zebrafish
- Authors
- Saera-Vila, A., Kasprick, D.S., Junttila, T.L., Grzegorski, S.J., Louie, K.W., Chiari, E.F., Kish, P.E., Kahana, A.
- ID
- ZDB-PUB-150801-2
- Date
- 2015
- Source
- Investigative ophthalmology & visual science 56: 4977-4993 (Journal)
- Registered Authors
- Grzegorski, Steven, Kahana, Alon, Kasprick, Dan, Kish, Phillip
- Keywords
- Cell reprogramming, Mesenchymal transition, Muscle injury, pax7, Progenitor cells, Satellite cell, Skeletal muscle, Stem cells
- MeSH Terms
-
- Animals
- Cell Cycle
- Follow-Up Studies
- Immunohistochemistry
- Microscopy, Electron, Transmission
- Muscle Cells/physiology*
- Muscle Cells/ultrastructure
- Myoblasts/physiology
- Myoblasts/ultrastructure
- Oculomotor Muscles/physiology*
- Oculomotor Muscles/surgery
- Oculomotor Muscles/ultrastructure
- Regeneration/physiology*
- Zebrafish
- PubMed
- 26230763 Full text @ Invest. Ophthalmol. Vis. Sci.
Citation
Saera-Vila, A., Kasprick, D.S., Junttila, T.L., Grzegorski, S.J., Louie, K.W., Chiari, E.F., Kish, P.E., Kahana, A. (2015) Myocyte Dedifferentiation Drives Extraocular Muscle Regeneration in Adult Zebrafish. Investigative ophthalmology & visual science. 56:4977-4993.
Abstract
Purpose The purpose of this study was to characterize the injury response of extraocular muscles (EOMs) in adult zebrafish.
Methods Adult zebrafish underwent lateral rectus (LR) muscle myectomy surgery to remove 50% of the muscle, followed by molecular and cellular characterization of the tissue response to the injury.
Results Following myectomy, the LR muscle regenerated an anatomically correct and functional muscle within 7 to 10 days post injury (DPI). Following injury, the residual muscle stump was replaced by a mesenchymal cell population that lost cell polarity and expressed mesenchymal markers. Next, a robust proliferative burst repopulated the area of the regenerating muscle. Regenerating cells expressed myod, identifying them as myoblasts. However, both immunofluorescence and electron microscopy failed to identify classic Pax7-positive satellite cells in control or injured EOMs. Instead, some proliferating nuclei were noted to express mef2c at the very earliest point in the proliferative burst, suggesting myonuclear reprogramming and dedifferentiation. Bromodeoxyuridine (BrdU) labeling of regenerating cells followed by a second myectomy without repeat labeling resulted in a twice-regenerated muscle broadly populated by BrdU-labeled nuclei with minimal apparent dilution of the BrdU signal. A double-pulse experiment using BrdU and 5-ethynyl-2'-deoxyuridine (EdU) identified double-labeled nuclei, confirming the shared progenitor lineage. Rapid regeneration occurred despite a cell cycle length of 19.1 hours, whereas 72% of the regenerating muscle nuclei entered the cell cycle by 48 hours post injury (HPI). Dextran lineage tracing revealed that residual myocytes were responsible for muscle regeneration.
Conclusions EOM regeneration in adult zebrafish occurs by dedifferentiation of residual myocytes involving a muscle-to-mesenchyme transition. A mechanistic understanding of myocyte reprogramming may facilitate novel approaches to the development of molecular tools for targeted therapeutic regeneration in skeletal muscle disorders and beyond.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping