The molecular appearance of native TRPM7 channel complexes identified by high-resolution proteomics
- University of Freiburg, Germany
- Ludwig Maximilian University of Munich, Germany
- University Linz, Austria
- Max Planck Institute for Experimental Medicine, Germany
- LMU Munich, Germany
Abstract
The transient receptor potential melastatin-subfamily member 7 (TRPM7) is a ubiquitously expressed membrane protein consisting of ion channel and protein kinase domains. TRPM7 plays a fundamental role in the cellular uptake of divalent cations such as Zn2+, Mg2+ and Ca2+, and thus shapes cellular excitability, plasticity and metabolic activity. The molecular appearance and operation of TRPM7 channel complexes in native tissues have remained unresolved. Here, we investigated the subunit composition of endogenous TRPM7 channels in rodent brain by multi-epitope affinity purification and high-resolution quantitative MS analysis. We found that native TRPM7 channels are high molecular-weight multi-protein complexes that contain the putative metal transporter proteins CNNM1-4 and a small G-protein ARL15. Heterologous reconstitution experiments confirmed the formation of TRPM7/CNNM/ARL15 ternary complexes and indicated that complex formation effectively and specifically impacts TRPM7 activity. These results open up new avenues towards a mechanistic understanding of the cellular regulation and function of TRPM7 channels.
Data availability
The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier PXD025279 and DOI: 10.6019/PXD025279.
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (TRR 152 P15)
- Vladimir Chubanov
Deutsche Forschungsgemeinschaft (TRR 152 P15)
- Thomas Gudermann
Deutsche Forschungsgemeinschaft (TRR 152 P02)
- Bernd Fakler
Deutsche Forschungsgemeinschaft (TRR 152 P02)
- Uwe Schulte
Deutsche Forschungsgemeinschaft (SFB 1328 P15)
- Annette Nicke
Deutsche Forschungsgemeinschaft (SFB 1381)
- Bernd Fakler
Deutsche Forschungsgemeinschaft (Research Training Group 2338)
- Thomas Gudermann
Deutsche Forschungsgemeinschaft (Research Training Group 2338)
- Annette Nicke
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Kollewe et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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The molecular appearance of native TRPM7 channel complexes identified by high-resolution proteomics
eLife 10:e68544.
https://doi.org/10.7554/eLife.68544
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