Download MendeleyMolecular basis of Mg 2+ permeation through the human mitochondrial Mrs2 channel.
Li, M., Li, Y., Lu, Y., Li, J., Lu, X., Ren, Y., Wen, T., Wang, Y., Chang, S., Zhang, X., Yang, X., Shen, Y.(2023) Nat Commun 14: 4713-4713
- PubMed: 37543649
- DOI: https://doi.org/10.1038/s41467-023-40516-2
- Primary Citation of Related Structures:
8IP3, 8IP4, 8IP5, 8IP6 - PubMed Abstract:
Mitochondrial RNA splicing 2 (Mrs2), a eukaryotic CorA ortholog, enables Mg 2+ to permeate the inner mitochondrial membrane and plays an important role in mitochondrial metabolic function. However, the mechanism by which Mrs2 permeates Mg 2+ remains unclear. Here, we report four cryo-electron microscopy (cryo-EM) reconstructions of Homo sapiens Mrs2 (hMrs2) under various conditions. All of these hMrs2 structures form symmetrical pentamers with very similar pentamer and protomer conformations. A special structural feature of Cl - -bound R-ring, which consists of five Arg332 residues, was found in the hMrs2 structure. Molecular dynamics simulations and mitochondrial Mg 2+ uptake assays show that the R-ring may function as a charge repulsion barrier, and Cl - may function as a ferry to jointly gate Mg 2+ permeation in hMrs2. In addition, the membrane potential is likely to be the driving force for Mg 2+ permeation. Our results provide insights into the channel assembly and Mg 2+ permeation of hMrs2.
Organizational Affiliation:
State Key Laboratory of Medicinal Chemical Biology and Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin, 300350, China.
