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bioRxiv · 10.1101/2022.12.20.521030

A system for inducible mitochondria-specific protein degradation in vivo

Sanyal, S.·Kouznetsova, A.·Bjorkegren, C.
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Abstract

Targeted protein degradation systems developed for eukaryotes employ cytoplasmic machineries to perform proteolysis. This has prevented mitochondria-specific analysis of genome maintaining proteins that localize to both mitochondria and nucleus. Here, we present an inducible mitochondria-specific protein degradation system in Saccharomyces cerevisiae based on the Mesoplasma florum Lon (mf-Lon) protease and its corresponding ssrA tag (called PDT). We show that mitochondrially targeted mf-Lon protease efficiently and selectively degrades a PDT-tagged reporter protein localized to the mitochondrial matrix. The degradation can be induced by depleting adenine from the medium and tuned by altering the promoter strength of the MF-LON gene. Finally, we demonstrate that mf-Lon degrades endogenous, dually localized proteins inside mitochondria. In summary, our system is an efficient tool for analysis of intricate mitochondria-nuclear crosstalk essential for proper mitochondrial function. One-Sentence SummaryMitochondria-specific protein degradation of dually localized proteins

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Sanyal, S., Kouznetsova, A., Bjorkegren, C.. 2022-12-20. A system for inducible mitochondria-specific protein degradation in vivo. https://doi.org/10.1101/2022.12.20.521030

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