National Natural Science Foundation of China (NSFC)
32271261
中国
引用
ジャーナル: Nature / 年: 2025 タイトル: Structure and assembly of the dystrophin glycoprotein complex. 著者: Li Wan / Xiaofei Ge / Qikui Xu / Gaoxingyu Huang / Tiandi Yang / Kevin P Campbell / Zhen Yan / Jianping Wu / 要旨: 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 ...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. Dysfunction of dystrophin and its associated proteins results in muscular dystrophy, a disorder characterized by progressive muscle weakness and degeneration. 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. 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.