Closed and open structures of the eukaryotic magnesium channel Mrs2 reveal the auto-ligand-gating regulation mechanism
(2024) In Nature Structural and Molecular Biology- Abstract
The CorA/Mrs2 family of pentameric proteins are cardinal for the influx of Mg2+ across cellular membranes, importing the cation to mitochondria in eukaryotes. Yet, the conducting and regulation mechanisms of permeation remain elusive, particularly for the eukaryotic Mrs2 members. Here, we report closed and open Mrs2 cryo-electron microscopy structures, accompanied by functional characterization. Mg2+ flux is permitted by a narrow pore, gated by methionine and arginine residues in the closed state. Transition between the conformations is orchestrated by two pairs of conserved sensor-serving Mg2+-binding sites in the mitochondrial matrix lumen, located in between monomers. At lower levels of... (More)
The CorA/Mrs2 family of pentameric proteins are cardinal for the influx of Mg2+ across cellular membranes, importing the cation to mitochondria in eukaryotes. Yet, the conducting and regulation mechanisms of permeation remain elusive, particularly for the eukaryotic Mrs2 members. Here, we report closed and open Mrs2 cryo-electron microscopy structures, accompanied by functional characterization. Mg2+ flux is permitted by a narrow pore, gated by methionine and arginine residues in the closed state. Transition between the conformations is orchestrated by two pairs of conserved sensor-serving Mg2+-binding sites in the mitochondrial matrix lumen, located in between monomers. At lower levels of Mg2+, these ions are stripped, permitting an alternative, symmetrical shape, maintained by the RDLR motif that replaces one of the sensor site pairs in the open conformation. Thus, our findings collectively establish the molecular basis for selective Mg2+ influx of Mrs2 and an auto-ligand-gating regulation mechanism.
(Less)
- author
- organization
-
- Membrane Protein Structural Biology (research group)
- Biophysical Chemistry
- EXODIAB: Excellence of Diabetes Research in Sweden
- Medical Structural Biology (research group)
- LUCC: Lund University Cancer Centre
- BioCARE: Biomarkers in Cancer Medicine improving Health Care, Education and Innovation
- LTH Profile Area: Food and Bio
- publishing date
- 2024
- type
- Contribution to journal
- publication status
- in press
- subject
- in
- Nature Structural and Molecular Biology
- publisher
- Nature Publishing Group
- external identifiers
-
- pmid:39609652
- scopus:85210485440
- ISSN
- 1545-9993
- DOI
- 10.1038/s41594-024-01432-1
- language
- English
- LU publication?
- yes
- additional info
- Publisher Copyright: © The Author(s) 2024.
- id
- ba69a286-a91d-4b7f-921d-19a3de879309
- date added to LUP
- 2025-01-15 13:27:40
- date last changed
- 2025-07-03 03:44:11
@article{ba69a286-a91d-4b7f-921d-19a3de879309, abstract = {{<p>The CorA/Mrs2 family of pentameric proteins are cardinal for the influx of Mg<sup>2+</sup> across cellular membranes, importing the cation to mitochondria in eukaryotes. Yet, the conducting and regulation mechanisms of permeation remain elusive, particularly for the eukaryotic Mrs2 members. Here, we report closed and open Mrs2 cryo-electron microscopy structures, accompanied by functional characterization. Mg<sup>2+</sup> flux is permitted by a narrow pore, gated by methionine and arginine residues in the closed state. Transition between the conformations is orchestrated by two pairs of conserved sensor-serving Mg<sup>2+</sup>-binding sites in the mitochondrial matrix lumen, located in between monomers. At lower levels of Mg<sup>2+</sup>, these ions are stripped, permitting an alternative, symmetrical shape, maintained by the RDLR motif that replaces one of the sensor site pairs in the open conformation. Thus, our findings collectively establish the molecular basis for selective Mg<sup>2+</sup> influx of Mrs2 and an auto-ligand-gating regulation mechanism.</p>}}, author = {{Li, Ping and Liu, Shiyan and Wallerstein, Johan and Villones, Rhiza Lyne E. and Huang, Peng and Lindkvist-Petersson, Karin and Meloni, Gabriele and Lu, Kefeng and Steen Jensen, Kristine and Liin, Sara I. and Gourdon, Pontus}}, issn = {{1545-9993}}, language = {{eng}}, publisher = {{Nature Publishing Group}}, series = {{Nature Structural and Molecular Biology}}, title = {{Closed and open structures of the eukaryotic magnesium channel Mrs2 reveal the auto-ligand-gating regulation mechanism}}, url = {{http://dx.doi.org/10.1038/s41594-024-01432-1}}, doi = {{10.1038/s41594-024-01432-1}}, year = {{2024}}, }