The structure of the N-terminal region of murine skeletal muscle alpha-dystroglycan discloses a modular architecture.
Dystroglycan (DG) is a cell surface receptor consisting of two subunits: alpha-dystroglycan, extracellular and highly glycosylated, and beta-dystroglycan, spanning the cell membrane. It is a pivotal member of the dystrophin-glycoprotein complex and is involved in a wide variety of important cellular processes such as the stabilization of the muscle fiber sarcolemma or the clustering of acetylcholine receptors. We report the 2.3-A resolution crystal structure of the murine skeletal muscle N-terminal alpha-DG region, which confirms the presence of two autonomous domains; the first finally identified as an Ig-like and the second resembling ribosomal RNA-binding proteins. Solid-phase laminin binding assays show the occurrence of protein-protein type of interactions involving the Ig-like domain of alpha-DG.
Bozic
Damir
D
Biochemisches Institut der Universität Zürich, Zürich 8044, Switzerland. damir.bozic@mat.ethz.ch
Sciandra
Francesca
F
Lamba
Doriano
D
Brancaccio
Andrea
A
D000818:Animals; D019921:Biotinylation; D018360:Crystallography, X-Ray; D049030:Dystroglycans / Q000737:chemistry*; D004583:Electrons; D007797:Laminin / Q000737:chemistry; D051379:Mice; D008958:Models, Molecular; D018485:Muscle Fibers, Skeletal / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D012313:RNA / Q000737:chemistry; D011994:Recombinant Proteins / Q000737:chemistry; D012984:Software
D007797:Laminin; D011994:Recombinant Proteins; D049030:Dystroglycans; D012313:RNA