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Author Spotlight: Advancing Mitochondrial Research - mtHyper7 Biosensor for Subcellular Analysis
Published on: June 2, 2023
The small yeast GTPase Rho5 requires specific mitochondrial outer membrane proteins for translocation under oxidative
Linnet Bischof1, Franziska Schweitzer1, Hans-Peter Schmitz1
1Universität Osnabrück, Fachbereich Biologie/Chemie, AG Genetik, Barbarastr. 11, Osnabrück D-49076, Germany.
Abstract:
Yeast Rho5 is a small GTPase which mediates the response to nutrient and oxidative stress, and triggers mitophagy and apoptosis. We here studied the rapid translocation of a GFP-tagged Rho5 to mitochondria under such stress conditions by live-cell fluorescence microscopy in the background of strains lacking different mitochondrial outer membrane proteins (MOMP). Fun14, Msp1 and Alo1 were found to be required for efficient recruitment of the GTPase, whereas translocation of Dck1 and Lmo1, the subunits of its dimeric GDP/GTP exchange factor (GEF), remained unaffected. An influence of the voltage-dependent anion channel (VDAC) Por1 on the association of GFP-Rho5 with mitochondria under oxidative stress conditions appeared to be strain-dependent. However, epistasis analyses and bimolecular fluorescence complementation (BiFC) studies indicate a genetic and physical interaction. All four strains lacking a single MOMP were investigated for their effect on mitophagy.
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