What happens when dystrophin is dysfunctional?
Skeletal and cardiac muscle cells without enough functional dystrophin become damaged as the muscles repeatedly contract and relax with use. The damaged cells weaken and die over time, causing the characteristic muscle weakness and heart problems seen in Duchenne and Becker muscular dystrophy.
What makes the dystrophin of people with DMD dysfunctional?
DMD occurs because the mutated DMD gene fails to produce virtually any functional dystrophin. Individuals with BMD genetic mutations make dystrophin that is partially functional, which protects their muscles from degenerating as badly or as quickly as in DMD.
Which three domains of dystrophin are critical for its function?
Dystrophin structure overview Dystrophin protein has four main functional domains; an actin-binding amino-terminal domain (ABD1), a central rod domain, a cysteine-rich domain and a carboxyl-terminus (Figure 2A).
Why is DMD more common in males?
The DMD gene is located on the X chromosome, so Duchenne muscular dystrophy is an X-linked disease and mostly affects males because they have only one copy of the X-chromosome.
What kind of glycoprotein is dystrophin associated with?
In skeletal and cardiac muscle, dystrophin is associated with a large oligomeric complex of sarcolemmal glycoproteins. This dystrophin–glycoprotein complex is composed of five glycoproteins (35, 43 doublet, 50, and 156 kd) and two proteins (25 and 59 kd).
How does the dystrophin complex stabilize the plasma membrane?
The dystrophin complex stabilizes the plasma membrane of striated muscle cells. Loss of function mutations in the genes encoding dystrophin, or the associated proteins, trigger instability of the plasma membrane, and myofiber loss.
Who are the authors of the dystrophin complex?
The Dystrophin Complex: Structure, Function, and Implications for Therapy Compr Physiol. 2015 Jul 1;5(3):1223-39.doi: 10.1002/cphy.c140048. Authors Quan Q Gao 1 , Elizabeth M McNally 2 Affiliations
What are the results of dystrophin immunostaining in skeletal muscle?
The results of immunostaining in both skeletal and cardiac muscle showed normal reactivity for antibodies directed against the three portions of the dystrophin molecule ( Figure 2 ). Immunostaining of adhalin was drastically reduced in skeletal muscle, but a trace amount of adhalin was still present.
