This comprises the non-covalently-associated extracellular α-DG, that interacts with laminin in the BM, and the transmembrane β-DG, that interacts principally with dystrophin to connect to the actin cytoskeleton.
Co-IP MS identification of proteins from cardiac and skeletal muscle that interact with dystrophin (a protein responsible for a number of myopathies) has also led to the identification of tissue-specific signaling pathways that seem to play a role in cardiac disease and muscular dystrophy [ 73].
Moreover, these authors also demonstrate that N-glycosylation and the cysteine-rich domain of δ-sarcoglycan are crucial for the localisation of sarcoglycans to the cell membrane, and suggest that the intracellular tails of β- and δ-sarcoglycan interact with dystrophin (Ref. 29).
The C-terminal cytoplasmic tail of β-dystroglycan interacts with dystrophin which binds to the actin cytoskeleton (11).
β-DG interacts with dystrophin, which in turn binds to actin filaments.
In m. vastus lateralis, nNOS is anchored at the sarcolemma by binding of a PDZ domain to α1-syntrophin, a member of the dystrophin-glycoprotein complex (DGC), and interacting with dystrophin [ 19, 20].
3) Although all the proteins interacting with dystrophin are well conserved during vertebrate evolution, there is no evidence in the paper that rules out that the bound mobile dystrophin pool may be the consequence of a weaker interaction of human dystrophin with fish complex proteins and may not exist in human cells, or even in the zebrafish embryo expressing a wt level of the fish protein.
β-Dystroglycan is a transmembrane protein that anchors the extracellular α-dystroglycan to the plasma membrane and interacts intracellularly with dystrophin (and/or utrophin, which can replace dystrophin) and syntrophin.
Therefore, it is believed that telethonin does not interact with the dystrophin associated complex [ 19].
α-Dystrobrevin is one of the components of the dystrophin-associated protein complex (DAPC) [ 7] and interacts specifically with dystrophin and syntrophin in skeletal muscle [ 8].
