Muscular dystrophy is the collective name for a group of genetic diseases that cause the progressive break down of muscle in the body. The diseases lead to weakness and subsequent loss of mobility. The heart, diaphragm, and gastrointestinal muscle may also be affected.
DMD is caused by a defect in the gene coding for dystrophin. Dystrophin is a structural protein that provides support in the muscle cells by anchoring the internal scaffolding of the cell (called the cytoskeleton) to the cell membrane. When the dystrophin gene is mutated the resulting protein is no longer fully functional. Over time the scaffolding pulls away from the cell membrane, causing the cell to collapse and die. This leads to the muscle wasting characteristics of DMD.We can model DMD and other muscular dystrophies by looking at fish that carry similar mutations to those found in humans. One such mutant is royal vegas casino called sapje and has a mutation in the dystrophin gene. Like in the human patients the muscle in the fish degenerates and dies.We can learn about how dystrophin functions in cells and in the whole organism using mutants such as sapje. We can also investigate possible treatments for the disease by screening potential drugs on the fish and looking for ‘rescue’ of the muscle damage.
To make large muscle fibres many single celled myocytes must fuse together to create what is called a syncytium, which may consist of thousands of individual cells. Normally a cell has one nucleus, but a syncytial cell has many nuclei, each contributed by the component myocytes.
The syncytium is important as it allows coordinated contraction across the whole muscle.