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The zebrafish dystrophic mutant softy maintains muscle fibre viability despite basement membrane rupture and muscle detachment.

ABSTRACT: The skeletal muscle basement membrane fulfils several crucial functions during development and in the mature myotome and defects in its composition underlie certain forms of muscular dystrophy. A major component of this extracellular structure is the laminin polymer, which assembles into a resilient meshwork that protects the sarcolemma during contraction. Here we describe a zebrafish mutant, softy, which displays severe embryonic muscle degeneration as a result of initial basement membrane failure. The softy phenotype is caused by a mutation in the lamb2 gene, identifying laminin beta2 as an essential component of this basement membrane. Uniquely, softy homozygotes are able to recover and survive to adulthood despite the loss of myofibre adhesion. We identify the formation of ectopic, stable basement membrane attachments as a novel means by which detached fibres are able to maintain viability. This demonstration of a muscular dystrophy model possessing innate fibre viability following muscle detachment suggests basement membrane augmentation as a therapeutic strategy to inhibit myofibre loss.

SUBMITTER: Jacoby AS

PROVIDER: S-EPMC2739150 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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The zebrafish dystrophic mutant softy maintains muscle fibre viability despite basement membrane rupture and muscle detachment.

Jacoby Arie S AS Busch-Nentwich Elisabeth E Bryson-Richardson Robert J RJ Hall Thomas E TE Berger Joachim J Berger Silke S Sonntag Carmen C Sachs Caroline C Geisler Robert R Stemple Derek L DL Currie Peter D PD

Development (Cambridge, England) 20091001 19

The skeletal muscle basement membrane fulfils several crucial functions during development and in the mature myotome and defects in its composition underlie certain forms of muscular dystrophy. A major component of this extracellular structure is the laminin polymer, which assembles into a resilient meshwork that protects the sarcolemma during contraction. Here we describe a zebrafish mutant, softy, which displays severe embryonic muscle degeneration as a result of initial basement membrane fail ...[more]

PMID: 19736328

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Dataset Information

The zebrafish dystrophic mutant softy maintains muscle fibre viability despite basement membrane rupture and muscle detachment.

Publications

The zebrafish dystrophic mutant softy maintains muscle fibre viability despite basement membrane rupture and muscle detachment.

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