Exon Skipping in a Dysf-Missense Mutant Mouse Model.

Limb girdle muscular dystrophy 2B (LGMD2B) is without treatment and caused by mutations in the dysferlin gene (DYSF). One-third is missense mutations leading to dysferlin aggregation and amyloid formation, in addition to defects in sarcolemmal repair and progressive muscle wasting. Dysferlin-null mouse models do not allow study of the consequences of missense mutations.

BMP signaling regulates satellite cell-dependent postnatal muscle growth.

Postnatal growth of skeletal muscle largely depends on the expansion and differentiation of resident stem cells, the so-called satellite cells. Here, we demonstrate that postnatal satellite cells express components of the bone morphogenetic protein (BMP) signaling machinery. Overexpression of noggin in postnatal mice (to antagonize BMP ligands), satellite cell-specific knockout of (the gene encoding the BMP transmembrane receptor) or overexpression of inhibitory SMAD6 decreased satellite cell proliferation and accretion during myofiber growth, and ultimately retarded muscle growth.

Rapid, scalable, and low-cost purification of recombinant adeno-associated virus produced by baculovirus expression vector system.

Recombinant adeno-associated viruses (rAAV) are largely used for gene transfer in research, preclinical developments, and clinical trials. Their broad in vivo biodistribution and long-term efficacy in postmitotic tissues make them good candidates for numerous gene transfer applications. Upstream processes able to produce large amounts of rAAV were developed, particularly those using baculovirus expression vector system.

In vivo dynamics of skeletal muscle Dystrophin in zebrafish embryos revealed by improved FRAP analysis.

Dystrophin forms an essential link between sarcolemma and cytoskeleton, perturbation of which causes muscular dystrophy. We analysed Dystrophin binding dynamics in vivo for the first time. Within maturing fibres of host zebrafish embryos, our analysis reveals a pool of diffusible Dystrophin and complexes bound at the fibre membrane.

Stem Cell-Mediated Exon Skipping of the Dystrophin Gene by the Bystander Effect.

Duchenne muscular dystrophy (DMD) is characterized by the loss of a functional dystrophin protein; the muscles of DMD patients progressively degenerate as a result of mechanical stress during contractions, and the condition eventually leads to premature death. By means antisense oligonucleotides (AONs), it is possible to modulate pre-mRNA splicing eliminating mutated exons and restoring dystrophin open reading frame. To overcome the hurdles in using AONs for therapeutic interventions, we exerted engineered human DMD stem cells with a lentivirus, which permanently and efficiently delivered the cloned AONs.