Structure and assembly of the dystrophin glycoprotein complex.
Wan, L., Ge, X., Xu, Q., Huang, G., Yang, T., Campbell, K.P., Yan, Z., Wu, J.(2025) Nature 637: 1252-1260
- PubMed: 39663450
- DOI: https://doi.org/10.1038/s41586-024-08310-2
- Primary Citation of Related Structures:
8YT8 - PubMed Abstract:
The dystrophin glycoprotein complex (DGC) has a crucial role in maintaining cell membrane stability and integrity by connecting the intracellular cytoskeleton with the surrounding extracellular matrix 1-3 . Dysfunction of dystrophin and its associated proteins results in muscular dystrophy, a disorder characterized by progressive muscle weakness and degeneration 4,5 . Despite the important roles of the DGC in physiology and pathology, its structural details remain largely unknown, hindering a comprehensive understanding of its assembly and function. Here we isolated the native DGC from mouse skeletal muscle and obtained its high-resolution structure. Our findings unveil a markedly divergent structure from the previous model of DGC assembly. Specifically, on the extracellular side, β-, γ- and δ-sarcoglycans co-fold to form a specialized, extracellular tower-like structure, which has a central role in complex assembly by providing binding sites for α-sarcoglycan and dystroglycan. In the transmembrane region, sarcoglycans and sarcospan flank and stabilize the single transmembrane helix of dystroglycan, rather than forming a subcomplex as previously proposed 6-8 . On the intracellular side, sarcoglycans and dystroglycan engage in assembly with the dystrophin-dystrobrevin subcomplex through extensive interaction with the ZZ domain of dystrophin. Collectively, these findings enhance our understanding of the structural linkage across the cell membrane and provide a foundation for the molecular interpretation of many muscular dystrophy-related mutations.
Organizational Affiliation:
Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, China.