Dystroglycan-α, a dystrophin-associated glycoprotein, is a functional agrin receptor

  title={Dystroglycan-$\alpha$, a dystrophin-associated glycoprotein, is a functional agrin receptor},
  author={Stephen H. Gee and Federica Alice Maria Montanaro and Michael H. Lindenbaum and Salvatore Carbonetto},

Dystroglycan Is a Dual Receptor for Agrin and Laminin-2 in Schwann Cell Membrane*

Results indicate that α-dystroglycan is a dual receptor for agrin and laminin-2 in the Schwann cell membrane.

AChR phosphorylation and aggregation induced by an agrin fragment that lacks the binding domain for alpha‐dystroglycan.

It is concluded that agrin‐induced AChR phosphorylation and aggregation are triggered by an agrin receptor that is distinct from alpha‐dystroglycan.

α-Dystroglycan Is a Laminin Receptor Involved in Extracellular Matrix Assembly on Myotubes and Muscle Cell Viability

It is suggested that α-DG is a functional LN receptor in situ which is required for deposition of LN on the cell and, further, implicate α- DG in the maintenance of myotube viability.

Alternative RNA splicing that determines agrin activity regulates binding to heparin and alpha-dystroglycan.

A model in which multiple distinct domains of agrin interact with both protein and sugar moieties of alpha-dystroglycan is proposed, which is consistent with a functional role for this interaction during synaptogenesis.

Agrin Is a High-affinity Binding Protein of Dystroglycan in Non-muscle Tissue*

Tissue distribution and binding affinities show that the agrin isoform expressed in non-muscle tissue is a high-affinity binding partner of dystroglycan and suggest that this interaction, like that between laminin and dystoglycan, may be important for the mechanical integrity of the tissue.

The Dystroglycan Complex Is Necessary for Stabilization of Acetylcholine Receptor Clusters at Neuromuscular Junctions and Formation of the Synaptic Basement Membrane

It is shown that myotubes differentiated from dystroglycan−/− embryonic stem cells are responsive to agrin, but produce acetylcholine receptor (AChR) clusters which are two to three times larger in area, about half as dense, and significantly less stable than those on dystoglycan+/+ myot tubes.

An Extracellular Pathway for Dystroglycan Function in Acetylcholine Receptor Aggregation and Laminin Deposition in Skeletal Myotubes*

It is discussed how DG may regulate synapses through extracellular signaling functions of its α subunit, which modulate the size and the microcluster density of agrin-induced acetylcholine receptor aggregates and are responsible for targeting laminin to these clusters.

Laminin and α-Dystroglycan Mediate Acetylcholine Receptor Aggregation via a MuSK-Independent Pathway

It is hypothesized that the interaction of LN with α-DG contributes to the growth and/or stabilization of AChR microaggregates into macroaggregate at the developing NMJ via a MuSK-independent mechanism.

Dystrophic phenotype induced in vitro by antibody blockade of muscle alpha-dystroglycan-laminin interaction.

The induction of a dystrophic phenotype in vitro is shown by treating primary mouse muscle cultures with a monoclonal antibody which blocks alpha-dystroglycan binding to laminin, which may be part of a signalling pathway for the maturation and maintenance of skeletal myofibres.



A role for the dystrophin-glycoprotein complex as a transmembrane linker between laminin and actin

The results support a role for the striated muscle dystrophin-glycoprotein complex in linking the actin- based cytoskeleton with the extracellular matrix and suggest that dystophin and dystroglycan may play substantially different functional roles in nonmuscle tissues.

Association of dystrophin-related protein with dystrophin-associated proteins in mdx mouse muscle

The results could provide a basis for the upregulation of DRP as a potential therapeutic approach in Duchenne muscular dystrophy and mdx muscle.

Localization of dystrophin relative to acetylcholine receptor domains in electric tissue and adult and cultured skeletal muscle

Results suggest that dystrophin may have a role in organization of AChR in electric tissue and, at the neuromuscular junction, its roles may be more related to organization of the junctional folds.

Different distributions of dystrophin and related proteins at nerve-muscle junctions.

DRP is more closely associated with AChRs than are dystrophin or beta-spectrin, according to immunofluorescence techniques used at rat nerve-muscle junctions.

Agrin induces phosphorylation of the nicotinic acetylcholine receptor

Clustering and immobilization of acetylcholine receptors by the 43-kD protein: a possible role for dystrophin-related protein

It is shown that AChRs present on the fibroblast cell surface prior to transfection of 43k are recruited into 43k-rich membrane domains, and cytoskeletal component, dystrophin related protein (DRP) contributed to the development of AChR clusters.

Dystrophin-glycoprotein complex and laminin colocalize to the sarcolemma and transverse tubules of cardiac muscle.

It is demonstrated that DAPs, dystrophin, and laminin colocalize to the sarcolemma in rabbit and sheep papillary myofibers as they do in skeletal my ofibers, implying that the protein composition and thus possibly some functions of T tubules in cardiac muscle are distinct from those of skeletal muscle.