Document Type
Journal Article
Publication Date
2014
Journal
Cell Death and Disease
Volume
Volume 5
Inclusive Pages
Article number e1306
Keywords
Membrane Proteins--metabolism; Muscle Proteins--metabolism; Myoblasts, Skeletal--metabolism; Sarcolemma--metabolism; Sphingomyelin Phosphodiesterase--secretion
Abstract
Dysferlin deficiency compromises the repair of injured muscle, but the underlying cellular mechanism remains elusive. To study this phenomenon, we have developed mouse and human myoblast models for dysferlinopathy. These dysferlinopathic myoblasts undergo normal differentiation but have a deficit in their ability to repair focal injury to their cell membrane. Imaging cells undergoing repair showed that dysferlin-deficit decreased the number of lysosomes present at the cell membrane, resulting in a delay and reduction in injury-triggered lysosomal exocytosis. We find repair of injured cells does not involve formation of intracellular membrane patch through lysosome–lysosome fusion; instead, individual lysosomes fuse with the injured cell membrane, releasing acid sphingomyelinase (ASM). ASM secretion was reduced in injured dysferlinopathic cells, and acute treatment with sphingomyelinase restored the repair ability of dysferlinopathic myoblasts and myofibers. Our results provide the mechanism for dysferlin-mediated repair of skeletal muscle sarcolemma and identify ASM as a potential therapy for dysferlinopathy.
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.
APA Citation
Defour, A., Van der Meulen, J.H., Bhat, R., Bigot, A., Bashir, R. et al. (2014). Dysferlin regulates cell membrane repair by facilitating injury-triggered acid sphingomyelinase secretion. Cell Death & Disease, 5:1306.
Peer Reviewed
1
Open Access
1
Comments
Reproduced with permission of Nature Journals, Cell Death & Disease.