Abstract

To detect cellular activities deep within the body using magnetic resonance platforms, magnetosomes are the ideal model of genetically-encoded nanoparticles. These membrane-bound iron biominerals produced by magnetotactic bacteria are highly regulated by approximately 30 genes; however, the number of magnetosome genes that are essential and/or constitute the root structure upon which biominerals form is largely undefined. To examine the possibility that key magnetosome genes may interact in a foreign environment, we expressed mamI and mamL as fluorescent fusion proteins in mammalian cells. Localization and potential protein-protein interaction(s) were investigated using confocal microscopy and fluorescence correlation spectroscopy (FCS). Enhanced green fluorescent protein (EGFP)-MamI and the red fluorescent Tomato-MamL displayed distinct intracellular localization, with net-like and punctate fluorescence, respectively. Remarkably, co-expression revealed co-localization of both fluorescent fusion proteins in the same punctate pattern. An interaction between MamI and MamL was confirmed by co-immunoprecipitation. In addition, changes in EGFP-MamI distribution were accompanied by acquisition of intracellular mobility which all Tomato-MamL structures displayed. Analysis of extracts from these cells by FCS was consistent with an interaction between fluorescent fusion proteins, including an increase in particle radius. Co-localization and interaction of MamI and MamL demonstrate that select magnetosome proteins may associate in mammalian cells.

Details

Title
Essential magnetosome proteins MamI and MamL from magnetotactic bacteria interact in mammalian cells
Author
Sun, Qin 1 ; Yu, Liu 2 ; Donnelly, Sarah C. 3 ; Fradin, Cécile 4 ; Thompson, R. Terry 5 ; Prato, Frank S. 6 ; Goldhawk, Donna E. 7 

 Lawson Research Institute, Imaging, London, Canada (GRID:grid.415847.b) (ISNI:0000 0001 0556 2414); Western University, Medical Biophysics, London, Canada (GRID:grid.39381.30) (ISNI:0000 0004 1936 8884); Western University, Collaborative Graduate Program in Molecular Imaging, London, Canada (GRID:grid.39381.30) (ISNI:0000 0004 1936 8884) 
 McMaster University, Physics & Astronomy, Hamilton, Canada (GRID:grid.25073.33) (ISNI:0000 0004 1936 8227) 
 Lawson Research Institute, Imaging, London, Canada (GRID:grid.415847.b) (ISNI:0000 0001 0556 2414) 
 McMaster University, Physics & Astronomy, Hamilton, Canada (GRID:grid.25073.33) (ISNI:0000 0004 1936 8227); McMaster University, Biochemistry & Biomedical Sciences, Hamilton, Canada (GRID:grid.25073.33) (ISNI:0000 0004 1936 8227) 
 Lawson Research Institute, Imaging, London, Canada (GRID:grid.415847.b) (ISNI:0000 0001 0556 2414); Western University, Medical Biophysics, London, Canada (GRID:grid.39381.30) (ISNI:0000 0004 1936 8884); Western University, Medical Imaging, London, Canada (GRID:grid.39381.30) (ISNI:0000 0004 1936 8884); Western University, Physics & Astronomy, London, Canada (GRID:grid.39381.30) (ISNI:0000 0004 1936 8884) 
 Lawson Research Institute, Imaging, London, Canada (GRID:grid.415847.b) (ISNI:0000 0001 0556 2414); Western University, Medical Biophysics, London, Canada (GRID:grid.39381.30) (ISNI:0000 0004 1936 8884); Western University, Collaborative Graduate Program in Molecular Imaging, London, Canada (GRID:grid.39381.30) (ISNI:0000 0004 1936 8884); Western University, Medical Imaging, London, Canada (GRID:grid.39381.30) (ISNI:0000 0004 1936 8884) 
 Lawson Research Institute, Imaging, London, Canada (GRID:grid.415847.b) (ISNI:0000 0001 0556 2414); Western University, Medical Biophysics, London, Canada (GRID:grid.39381.30) (ISNI:0000 0004 1936 8884); Western University, Collaborative Graduate Program in Molecular Imaging, London, Canada (GRID:grid.39381.30) (ISNI:0000 0004 1936 8884); Lawson Research Institute, Imaging Program, London, Canada (GRID:grid.415847.b) (ISNI:0000 0001 0556 2414) 
Pages
26292
Publication year
2024
Publication date
2024
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
3123173461
Copyright
© The Author(s) 2024. This work is published under http://creativecommons.org/licenses/by-nc-nd/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.