Muscular dystrophy in dysferlin-deficient mouse models.

Mutations in the dysferlin gene result in the development of a range of early adult-onset, progressive muscular dystrophies, collectively known as the dysferlinopathies. There is currently no effective treatment for these disorders. Several spontaneous and engineered alleles at the mouse dysferlin locus have been isolated and these dysferlin-deficient mouse strains are providing valuable insights into the role dysferlin plays in skeletal muscle physiology, heart function, and the regulation of the innate immune system.

Attenuated muscle regeneration is a key factor in dysferlin-deficient muscular dystrophy.

Skeletal muscle requires an efficient and active membrane repair system to overcome the rigours of frequent contraction. Dysferlin is a component of that system and absence of dysferlin causes muscular dystrophy (dysferlinopathy) characterized by adult onset muscle weakness, high serum creatine kinase levels and a prominent inflammatory infiltrate. We have observed that dysferlinopathy patient biopsies show an excess of immature fibres and therefore investigated the role of dysferlin in muscle regeneration.

Beta cells occur naturally in extrahepatic bile ducts of mice.

Insulin-secreting beta cells were thought to reside only in the pancreas. Here, we show that beta cells are also present in the extra-hepatic bile ducts of mice. They are characterised by insulin and C-peptide content, the presence of secretory granules that are immunoreactive for insulin, and the ducts exhibit glucose-stimulated insulin secretion.

In vitro culture of embryonic mouse intestinal epithelium: cell differentiation and introduction of reporter genes.

Background: Study of the normal development of the intestinal epithelium has been hampered by a lack of suitable model systems, in particular ones that enable the introduction of exogenous genes. Production of such a system would advance our understanding of normal epithelial development and help to shed light on the pathogenesis of intestinal neoplasia. The criteria for a reliable culture system include the ability to perform real time observations and manipulations in vitro, the preparation of wholemounts for immunostaining and the potential for introducing genes.