Hoffman, E. P., Brown, R. H. Jr. & Kunkel, L. M. Dystrophin: the protein product of the Duchenne muscular dystrophy locus. Cell 51, 919â928 (1987).
Mercuri, E., Bonnemann, C. G. & Muntoni, F. Muscular dystrophies. Lancet 394, 2025â2038 (2019).
Koenig, M. et al. Complete cloning of the Duchenne muscular dystrophy (DMD) cDNA and preliminary genomic organization of the DMD gene in normal and affected individuals. Cell 50, 509â517 (1987).
Campbell, K. P. & Kahl, S. D. Association of dystrophin and an integral membrane glycoprotein. Nature 338, 259â262 (1989).
Yoshida, M. & Ozawa, E. Glycoprotein complex anchoring dystrophin to sarcolemma. J. Biochem. 108, 748â752 (1990).
Ervasti, J. M. & Campbell, K. P. Membrane organization of the dystrophinâglycoprotein complex. Cell 66, 1121â1131 (1991).
Ibraghimov-Beskrovnaya, O. et al. Primary structure of dystrophin-associated glycoproteins linking dystrophin to the extracellular matrix. Nature 355, 696â702 (1992).
Gao, Q. Q. & McNally, E. M. The dystrophin complex: structure, function, and implications for therapy. Compr. Physiol. 5, 1223â1239 (2015).
Guiraud, S. et al. The pathogenesis and therapy of muscular dystrophies. Annu. Rev. Genomics Hum. Genet. 16, 281â308 (2015).
Le, S. et al. Dystrophin as a molecular shock absorber. ACS Nano 12, 12140â12148 (2018).
Pilgram, G. S., Potikanond, S., Baines, R. A., Fradkin, L. G. & Noordermeer, J. N. The roles of the dystrophin-associated glycoprotein complex at the synapse. Mol. Neurobiol. 41, 1â21 (2010).
Mirouse, V. Evolution and developmental functions of the dystrophin-associated protein complex: beyond the idea of a muscle-specific cell adhesion complex. Front. Cell. Dev. Biol. 11, 1182524 (2023).
Jayasinha, V. et al. Inhibition of dystroglycan cleavage causes muscular dystrophy in transgenic mice. Neuromuscul. Disord. 13, 365â375 (2003).
Endo, T. Glycobiology of α-dystroglycan and muscular dystrophy. J. Biochem. 157, 1â12 (2015).
Esapa, C. T., Bentham, G. R., Schroder, J. E., Kroger, S. & Blake, D. J. The effects of post-translational processing on dystroglycan synthesis and trafficking. FEBS Lett. 555, 209â216 (2003).
Johnson, K. et al. Detection of variants in dystroglycanopathy-associated genes through the application of targeted whole-exome sequencing analysis to a large cohort of patients with unexplained limb-girdle muscle weakness. Skelet. Muscle 8, 23 (2018).
Waite, A., Brown, S. C. & Blake, D. J. The dystrophinâglycoprotein complex in brain development and disease. Trends Neurosci. 35, 487â496 (2012).
Williamson, R. A. et al. Dystroglycan is essential for early embryonic development: disruption of Reichertâs membrane in Dag1-null mice. Hum. Mol. Genet. 6, 831â841 (1997).
Noguchi, S. et al. Mutations in the dystrophin-associated protein γ-sarcoglycan in chromosome 13 muscular dystrophy. Science 270, 819â822 (1995).
Roberds, S. L. et al. Missense mutations in the adhalin gene linked to autosomal recessive muscular dystrophy. Cell 78, 625â633 (1994).
Duclos, F. et al. Progressive muscular dystrophy in α-sarcoglycan-deficient mice. J. Cell Biol. 142, 1461â1471 (1998).
Lim, L. E. et al. β-Sarcoglycan: characterization and role in limb-girdle muscular dystrophy linked to 4q12. Nat. Genet. 11, 257â265 (1995).
Bonnemann, C. G. et al. β-Sarcoglycan (A3b) mutations cause autosomal recessive muscular dystrophy with loss of the sarcoglycan complex. Nat. Genet. 11, 266â273 (1995).
Nigro, V. et al. Autosomal recessive limb-girdle muscular dystrophy, LGMD2F, is caused by a mutation in the δ-sarcoglycan gene. Nat. Genet. 14, 195â198 (1996).
Noguchi, S., Wakabayashi, E., Imamura, M., Yoshida, M. & Ozawa, E. Formation of sarcoglycan complex with differentiation in cultured myocytes. Eur. J. Biochem. 267, 640â648 (2000).
Shi, W. et al. Specific assembly pathway of sarcoglycans is dependent on β- and δ-sarcoglycan. Muscle Nerve 29, 409â419 (2004).
Hemler, M. E. Tetraspanin proteins mediate cellular penetration, invasion, and fusion events and define a novel type of membrane microdomain. Annu. Rev. Cell Dev. Biol. 19, 397â422 (2003).
Crosbie, R. H., Heighway, J., Venzke, D. P., Lee, J. C. & Campbell, K. P. Sarcospan, the 25-kDa transmembrane component of the dystrophinâglycoprotein complex. J. Biol. Chem. 272, 31221â31224 (1997).
Lebakken, C. S. et al. Sarcospan-deficient mice maintain normal muscle function. Mol. Cell. Biol. 20, 1669â1677 (2000).
Marshall, J. L. et al. Dystrophin and utrophin expression require sarcospan: loss of α7 integrin exacerbates a newly discovered muscle phenotype in sarcospan-null mice. Hum. Mol. Genet. 21, 4378â4393 (2012).
Marshall, J. L. et al. Sarcospan-dependent Akt activation is required for utrophin expression and muscle regeneration. J. Cell Biol. 197, 1009â1027 (2012).
Peter, A. K., Miller, G. & Crosbie, R. H. Disrupted mechanical stability of the dystrophinâglycoprotein complex causes severe muscular dystrophy in sarcospan transgenic mice. J. Cell Sci. 120, 996â1008 (2007).
Suzuki, A. et al. Molecular organization at the glycoprotein-complex-binding site of dystrophin. Three dystrophin-associated proteins bind directly to the carboxy-terminal portion of dystrophin. Eur. J. Biochem. 220, 283â292 (1994).
Jung, D., Yang, B., Meyer, J., Chamberlain, J. S. & Campbell, K. P. Identification and characterization of the dystrophin anchoring site on β-dystroglycan. J. Biol. Chem. 270, 27305â27310 (1995).
Ponting, C. P., Blake, D. J., Davies, K. E., Kendrick-Jones, J. & Winder, S. J. ZZ and TAZ: new putative zinc fingers in dystrophin and other proteins. Trends Biochem. Sci 21, 11â13 (1996).
Rentschler, S. et al. The WW domain of dystrophin requires EF-hands region to interact with β-dystroglycan. Biol. Chem. 380, 431â442 (1999).
Ishikawa-Sakurai, M., Yoshida, M., Imamura, M., Davies, K. E. & Ozawa, E. ZZ domain is essentially required for the physiological binding of dystrophin and utrophin to β-dystroglycan. Hum. Mol. Genet. 13, 693â702 (2004).
Swiderski, K. et al. Phosphorylation within the cysteine-rich region of dystrophin enhances its association with β-dystroglycan and identifies a potential novel therapeutic target for skeletal muscle wasting. Hum. Mol. Genet. 23, 6697â6711 (2014).
Sadoulet-Puccio, H. M., Rajala, M. & Kunkel, L. M. Dystrobrevin and dystrophin: an interaction through coiled-coil motifs. Proc. Natl Acad. Sci. USA 94, 12413â12418 (1997).
Grady, R. M. et al. Role for α-dystrobrevin in the pathogenesis of dystrophin-dependent muscular dystrophies. Nat. Cell Biol. 1, 215â220 (1999).
Grady, R. M. et al. Maturation and maintenance of the neuromuscular synapse: genetic evidence for roles of the dystrophinâglycoprotein complex. Neuron 25, 279â293 (2000).
Grady, R. M. et al. Tyrosine-phosphorylated and nonphosphorylated isoforms of α-dystrobrevin: roles in skeletal muscle and its neuromuscular and myotendinous junctions. J. Cell Biol. 160, 741â752 (2003).
Ahn, A. H. & Kunkel, L. M. Syntrophin binds to an alternatively spliced exon of dystrophin. J. Cell Biol. 128, 363â371 (1995).
Huang, X. et al. Structure of a WW domain containing fragment of dystrophin in complex with β-dystroglycan. Nat. Struct. Mol. Biol. 7, 634â638 (2000).
Bozic, D., Sciandra, F., Lamba, D. & Brancaccio, A. The structure of the N-terminal region of murine skeletal muscle α-dystroglycan discloses a modular architecture. J. Biol. Chem. 279, 44812â44816 (2004).
Norwood, F. L., Sutherland-Smith, A. J., Keep, N. H. & Kendrick-Jones, J. The structure of the N-terminal actin-binding domain of human dystrophin and how mutations in this domain may cause Duchenne or Becker muscular dystrophy. Structure 8, 481â491 (2000).
Borgert, A., Foley, B. L. & Live, D. Contrasting the conformational effects of α-O-GalNAc and α-O-Man glycan protein modifications and their impact on the mucin-like region of α-dystroglycan. Glycobiology 31, 649â661 (2021).
Nagata, Y. & Burger, M. M. Wheat germ agglutinin. Molecular characteristics and specificity for sugar binding. J. Biol. Chem. 249, 3116â3122 (1974).
Dwyer, T. M. & Froehner, S. C. Direct binding of Torpedo syntrophin to dystrophin and the 87 kDa dystrophin homologue. FEBS Lett. 375, 91â94 (1995).
Steinbacher, S. et al. Crystal structure of P22 tailspike protein: interdigitated subunits in a thermostable trimer. Science 265, 383â386 (1994).
Stummeyer, K., Dickmanns, A., Muhlenhoff, M., Gerardy-Schahn, R. & Ficner, R. Crystal structure of the polysialic acid-degrading endosialidase of bacteriophage K1F. Nat. Struct. Mol. Biol. 12, 90â96 (2005).
Chan, Y. M., Bonnemann, C. G., Lidov, H. G. & Kunkel, L. M. Molecular organization of sarcoglycan complex in mouse myotubes in culture. J. Cell Biol. 143, 2033â2044 (1998).
Yis, U. et al. Childhood onset limb-girdle muscular dystrophies in the Aegean part of Turkey. Acta Myol. 37, 210â220 (2018).
Mitraki, A., Papanikolopoulou, K. & Van Raaij, M. J. Natural triple β-stranded fibrous folds. Adv. Protein Chem. 73, 97â124 (2006).
Yoshida, M. et al. Dissociation of the complex of dystrophin and its associated proteins into several unique groups by n-octyl β-d-glucoside. Eur. J. Biochem. 222, 1055â1061 (1994).
Yoshida, M. et al. The fourth component of the sarcoglycan complex. FEBS Lett. 403, 143â148 (1997).
Macao, B., Johansson, D. G., Hansson, G. C. & Hard, T. Autoproteolysis coupled to protein folding in the SEA domain of the membrane-bound MUC1 mucin. Nat. Struct. Mol. Biol. 13, 71â76 (2006).
Holm, L., Laiho, A., Toronen, P. & Salgado, M. DALI shines a light on remote homologs: one hundred discoveries. Protein Sci. 32, e4519 (2023).
Vickers, C. et al. Endo-fucoidan hydrolases from glycoside hydrolase family 107 (GH107) display structural and mechanistic similarities to α-l-fucosidases from GH29. J. Biol. Chem. 293, 18296â18308 (2018).
Crosbie, R. H. et al. Molecular and genetic characterization of sarcospan: insights into sarcoglycanâsarcospan interactions. Hum. Mol. Genet. 9, 2019â2027 (2000).
Fraiberg, M., Borovok, I., Bayer, E. A., Weiner, R. M. & Lamed, R. Cadherin domains in the polysaccharide-degrading marine bacterium Saccharophagus degradans 2-40 are carbohydrate-binding modules. J. Bacteriol. 193, 283â285 (2011).
Cao, L. et al. CHDL: a cadherin-like domain in Proteobacteria and Cyanobacteria. FEMS Microbiol. Lett. 251, 203â209 (2005).
Bork, P. & Patthy, L. The SEA module: a new extracellular domain associated with O-glycosylation. Protein Sci. 4, 1421â1425 (1995).
Hemler, M. E. Tetraspanin functions and associated microdomains. Nat. Rev. Mol. Cell Biol. 6, 801â811 (2005).
Charrin, S., Jouannet, S., Boucheix, C. & Rubinstein, E. Tetraspanins at a glance. J. Cell Sci. 127, 3641â3648 (2014).
Susa, K. J., Kruse, A. C. & Blacklow, S. C. Tetraspanins: structure, dynamics, and principles of partner-protein recognition. Trends Cell Biol. https://doi.org/10.1016/j.tcb.2023.09.003 (2023).
Miller, G., Wang, E. L., Nassar, K. L., Peter, A. K. & Crosbie, R. H. Structural and functional analysis of the sarcoglycanâsarcospan subcomplex. Exp. Cell. Res. 313, 639â651 (2007).
Crosbie, R. H. et al. Membrane targeting and stabilization of sarcospan is mediated by the sarcoglycan subcomplex. J. Cell Biol. 145, 153â165 (1999).
Peter, A. K., Marshall, J. L. & Crosbie, R. H. Sarcospan reduces dystrophic pathology: stabilization of the utrophinâglycoprotein complex. J. Cell Biol. 183, 419â427 (2008).
Miller, G., Peter, A. K., Espinoza, E., Heighway, J. & Crosbie, R. H. Over-expression of Microspan, a novel component of the sarcoplasmic reticulum, causes severe muscle pathology with triad abnormalities. J. Muscle Res. Cell Motil. 27, 545â558 (2006).
Peter, A. K. et al. Nanospan, an alternatively spliced isoform of sarcospan, localizes to the sarcoplasmic reticulum in skeletal muscle and is absent in limb girdle muscular dystrophy 2F. Skelet. Muscle 7, 11 (2017).
Yoshida, M. et al. Biochemical evidence for association of dystrobrevin with the sarcoglycanâsarcospan complex as a basis for understanding sarcoglycanopathy. Hum. Mol. Genet. 9, 1033â1040 (2000).
Rafael, J. A. et al. Forced expression of dystrophin deletion constructs reveals structure-function correlations. J. Cell Biol. 134, 93â102 (1996).
Crawford, G. E. et al. Assembly of the dystrophin-associated protein complex does not require the dystrophin COOH-terminal domain. J. Cell Biol. 150, 1399â1410 (2000).
Yoder, M. D., Keen, N. T. & Jurnak, F. New domain motif: the structure of pectate lyase C, a secreted plant virulence factor. Science 260, 1503â1507 (1993).
Emsley, P., Charles, I. G., Fairweather, N. F. & Isaacs, N. W. Structure of Bordetella pertussis virulence factor P.69 pertactin. Nature 381, 90â92 (1996).
Petersen, T. N., Kauppinen, S. & Larsen, S. The crystal structure of rhamnogalacturonase A from Aspergillus aculeatus: a right-handed parallel β helix. Structure 5, 533â544 (1997).
Gibbs, E. M. et al. High levels of sarcospan are well tolerated and act as a sarcolemmal stabilizer to address skeletal muscle and pulmonary dysfunction in DMD. Hum. Mol. Genet. 25, 5395â5406 (2016).
Parvatiyar, M. S. et al. Sarcospan regulates cardiac isoproterenol response and prevents Duchenne muscular dystrophy-associated cardiomyopathy. J. Am. Heart Assoc. 4, e002481 (2015).
Holt, K. H. et al. Functional rescue of the sarcoglycan complex in the BIO 14.6 hamster using δ-sarcoglycan gene transfer. Mol. Cell 1, 841â848 (1998).
Roberts, T. C., Wood, M. J. A. & Davies, K. E. Therapeutic approaches for Duchenne muscular dystrophy. Nat. Rev. Drug Discov. 22, 917â934 (2023).
Yue, Y., Liu, M. & Duan, D. C-terminal-truncated microdystrophin recruits dystrobrevin and syntrophin to the dystrophin-associated glycoprotein complex and reduces muscular dystrophy in symptomatic utrophin/dystrophin double-knockout mice. Mol. Ther. 14, 79â87 (2006).
Mitchell, R. D., Palade, P. & Fleischer, S. Purification of morphologically intact triad structures from skeletal muscle. J. Cell Biol. 96, 1008â1016 (1983).
Ervasti, J. M., Kahl, S. D. & Campbell, K. P. Purification of dystrophin from skeletal muscle. J. Biol. Chem. 266, 9161â9165 (1991).
Mastronarde, D. N. Automated electron microscope tomography using robust prediction of specimen movements. J. Struct. Biol. 152, 36â51 (2005).
Zheng, S. Q. et al. MotionCor2: anisotropic correction of beam-induced motion for improved cryo-electron microscopy. Nat. Methods 14, 331â332 (2017).
Rohou, A. & Grigorieff, N. CTFFIND4: fast and accurate defocus estimation from electron micrographs. J. Struct. Biol. 192, 216â221 (2015).
Zivanov, J. et al. New tools for automated high-resolution cryo-EM structure determination in RELION-3. eLife 7, e42166 (2018).
Kimanius, D., Dong, L., Sharov, G., Nakane, T. & Scheres, S. H. W. New tools for automated cryo-EM single-particle analysis in RELION-4.0. Biochem. J. 478, 4169â4185 (2021).
Punjani, A., Rubinstein, J. L., Fleet, D. J. & Brubaker, M. A. cryoSPARC: algorithms for rapid unsupervised cryo-EM structure determination. Nat. Methods 14, 290â296 (2017).
Bepler, T. et al. Positive-unlabeled convolutional neural networks for particle picking in cryo-electron micrographs. Nat. Methods 16, 1153â1160 (2019).
Kimanius, D. et al. Data-driven regularization lowers the size barrier of cryo-EM structure determination. Nat Methods 21, 1216-1221, doi:10.1038/s41592-024-02304-8 (2024).
Punjani, A., Zhang, H. & Fleet, D. J. Non-uniform refinement: adaptive regularization improves single-particle cryo-EM reconstruction. Nat. Methods 17, 1214â1221 (2020).
Chen, S. et al. High-resolution noise substitution to measure overfitting and validate resolution in 3D structure determination by single particle electron cryomicroscopy. Ultramicroscopy 135, 24â35 (2013).
Rosenthal, P. B. & Henderson, R. Optimal determination of particle orientation, absolute hand, and contrast loss in single-particle electron cryomicroscopy. J. Mol. Biol. 333, 721â745 (2003).
Jumper, J. et al. Highly accurate protein structure prediction with AlphaFold. Nature 596, 583â589 (2021).
Mirdita, M. et al. ColabFold: making protein folding accessible to all. Nat. Methods 19, 679â682 (2022).
Pettersen, E. F. et al. UCSF Chimeraâa visualization system for exploratory research and analysis. J. Comput. Chem. 25, 1605â1612 (2004).
Abramson, J. et al. Accurate structure prediction of biomolecular interactions with AlphaFold 3. Nature https://doi.org/10.1038/s41586-024-07487-w (2024).
Emsley, P., Lohkamp, B., Scott, W. G. & Cowtan, K. Features and development of Coot. Acta Crystallogr. D Biol. Crystallogr. 66, 486â501 (2010).
Buchan, D. W. A. & Jones, D. T. The PSIPRED Protein Analysis Workbench: 20 years on. Nucleic Acids Res. 47, W402âW407 (2019).
Adams, P. D. et al. PHENIX: a comprehensive Python-based system for macromolecular structure solution. Acta Crystallogr. D Biol. Crystallogr. 66, 213â221 (2010).
Chen, V. B. et al. MolProbity: all-atom structure validation for macromolecular crystallography. Acta Crystallogr. D Biol. Crystallogr. 66, 12â21 (2010).
Goddard, T. D. et al. UCSF ChimeraX: meeting modern challenges in visualization and analysis. Protein Sci. 27, 14â25 (2018).
Robert, X. & Gouet, P. Deciphering key features in protein structures with the new ENDscript server. Nucleic Acids Res. 42, W320âW324 (2014).
Edgar, R. C. MUSCLE: multiple sequence alignment with high accuracy and high throughput. Nucleic Acids Res. 32, 1792â1797 (2004).