Dystroglycan is one of the dystrophin-associated glycoproteins, which is encoded by a 5.5 kb transcript in human. The protein product is cleaved into two non-covalently associated subunits, [alpha] (N-terminal) and [beta] (C-terminal). In skeletal mu ...
Dystroglycan is one of the dystrophin-associated glycoproteins, which is encoded by a 5.5 kb transcript in human. The protein product is cleaved into two non-covalently associated subunits, [alpha] (N-terminal) and [beta] (C-terminal). In skeletal muscle the dystroglycan complex works as a transmembrane linkage between the extracellular matrix and the cytoskeleton. [alpha]-dystroglycan is extracellular and binds to merosin ([alpha]-2 laminin) in the basement membrane, while [beta]-dystroglycan is a transmembrane protein and binds to dystrophin, which is a large rod-like cytoskeletal protein, absent in Duchenne muscular dystrophy patients. Dystrophin binds to intracellular actin cables. In this way, the dystroglycan complex, which links the extracellular matrix to the intracellular actin cables, is thought to provide structural integrity in muscle tissues. The dystroglycan complex is also known to serve as an agrin receptor in muscle, where it may regulate agrin-induced acetylcholine receptor clustering at the neuromuscular junction. There is also evidence which suggests the function of dystroglycan as a part of the signal transduction pathway because it is shown that Grb2, a mediator of the Ras-related signal pathway, can interact with the cytoplasmic domain of dystroglycan. In general, aberrant expression of dystrophin-associated protein complex underlies the pathogenesis of Duchenne muscular dystrophy, Becker muscular dystrophy and severe childhood autosomal recessive muscular dystrophy. Interestingly, no genetic disease has been described for either [alpha]- or [beta]-dystroglycan. Dystroglycan is widely distributed in non-muscle tissues as well as in muscle tissues. During epithelial morphogenesis of kidney, the dystroglycan complex is shown to act as a receptor for the basement membrane. Dystroglycan expression in mouse brain and neural retina has also been reported. However, the physiological role of dystroglycan in non-muscle tissues has remained unclear [1]. This entry represents the fourth alpha/beta domain of dystroglycan which is homologous to its second domain.
Members of this family adopt a helix-loop-helix motif, as per other EF hand domains. However, since they do not contain the canonical pattern of calcium binding residues found in many EF hand domains, they do not bind calcium ions. The main function ...
Members of this family adopt a helix-loop-helix motif, as per other EF hand domains. However, since they do not contain the canonical pattern of calcium binding residues found in many EF hand domains, they do not bind calcium ions. The main function of this domain is the provision of specificity in beta-dystroglycan recognition, though in dystrophin it serves an additional role: stabilisation of the WW domain (Pfam:PF00397), enhancing dystroglycan binding [1].
Zinc finger present in dystrophin, CBP/p300. ZZ in dystrophin binds calmodulin. Putative zinc finger; binding not yet shown. Four to six cysteine residues in its sequence are responsible for coordinating zinc ions, to reinforce the structure [2].
Members of this family adopt a helix-loop-helix motif, as per other EF hand domains. However, since they do not contain the canonical pattern of calcium binding residues found in many EF hand domains, they do not bind calcium ions. The main function ...
Members of this family adopt a helix-loop-helix motif, as per other EF hand domains. However, since they do not contain the canonical pattern of calcium binding residues found in many EF hand domains, they do not bind calcium ions. The main function of this domain is the provision of specificity in beta-dystroglycan recognition, though in dystrophin it serves an additional role: stabilisation of the WW domain (Pfam:PF00397), enhancing dystroglycan binding [1].
Members of this family adopt a helix-loop-helix motif, as per other EF hand domains. However, since they do not contain the canonical pattern of calcium binding residues found in many EF hand domains, they do not bind calcium ions. The main function ...
Members of this family adopt a helix-loop-helix motif, as per other EF hand domains. However, since they do not contain the canonical pattern of calcium binding residues found in many EF hand domains, they do not bind calcium ions. The main function of this domain is the provision of specificity in beta-dystroglycan recognition, though in dystrophin it serves an additional role: stabilisation of the WW domain (Pfam:PF00397), enhancing dystroglycan binding [1].
Members of this family adopt a helix-loop-helix motif, as per other EF hand domains. However, since they do not contain the canonical pattern of calcium binding residues found in many EF hand domains, they do not bind calcium ions. The main function ...
Members of this family adopt a helix-loop-helix motif, as per other EF hand domains. However, since they do not contain the canonical pattern of calcium binding residues found in many EF hand domains, they do not bind calcium ions. The main function of this domain is the provision of specificity in beta-dystroglycan recognition, though in dystrophin it serves an additional role: stabilisation of the WW domain (Pfam:PF00397), enhancing dystroglycan binding [1].
Sarcoglycans are a subcomplex of transmembrane proteins which are part of the dystrophin-glycoprotein complex. They are expressed in the skeletal, cardiac and smooth muscle. Although numerous studies have been conducted on the sarcoglycan subcomplex ...
Sarcoglycans are a subcomplex of transmembrane proteins which are part of the dystrophin-glycoprotein complex. They are expressed in the skeletal, cardiac and smooth muscle. Although numerous studies have been conducted on the sarcoglycan subcomplex in skeletal and cardiac muscle, the manner of the distribution and localisation of these proteins along the nonjunctional sarcolemma is not clear [1]. This family contains alpha and epsilon members. This entry represents the N-terminal domain.
Sarcoglycans are a subcomplex of transmembrane proteins which are part of the dystrophin-glycoprotein complex. They are expressed in the skeletal, cardiac and smooth muscle. Although numerous studies have been conducted on the sarcoglycan subcomplex ...
Sarcoglycans are a subcomplex of transmembrane proteins which are part of the dystrophin-glycoprotein complex. They are expressed in the skeletal, cardiac and smooth muscle. Although numerous studies have been conducted on the sarcoglycan subcomplex in skeletal and cardiac muscle, the manner of the distribution and localisation of these proteins along the nonjunctional sarcolemma is not clear [1]. This family contains alpha and epsilon members and represents the second domain which has an Ig-like fold.
