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A Model Membrane Platform for Reconstituting Mitochondrial Membrane Dynamics
Published on: September 2, 2020
Mitochondrial membrane remodelling regulated by a conserved rhomboid protease
G Angus McQuibban1, Saroj Saurya, Matthew Freeman
1MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK.
Nature
|May 30, 2003
Summary
Yeast rhomboids, Rbd1p and Rbd2p, have novel roles beyond signaling. Rbd1p, located in mitochondria, cleaves Mgm1p, regulating mitochondrial membrane fusion and cellular respiration.
Area of Science:
- Biochemistry
- Cell Biology
- Molecular Genetics
Background:
- Rhomboid proteins are intramembrane serine proteases.
- They are known to activate epidermal growth factor receptor (EGFR) signaling in Drosophila.
- Conserved across evolution, rhomboids likely have roles beyond EGFR signaling.
Purpose of the Study:
- To investigate the function of rhomboid proteins in Saccharomyces cerevisiae.
- To identify substrates and cellular roles of yeast rhomboids, Rbd1p and Rbd2p.
- To explore the conservation and function of mitochondrial rhomboids.
Main Methods:
- Gene deletion and phenotypic analysis of yeast mutants.
- Subcellular localization studies of Rbd1p.
- Identification and characterization of Rbd1p substrates.
Main Results:
- Saccharomyces cerevisiae possesses two rhomboids: Rbd1p and Rbd2p.
- Rbd1p localizes to the inner mitochondrial membrane and is essential for respiration.
- Rbd1p cleaves cytochrome c peroxidase (Ccp1p) and Mgm1p, a key regulator of mitochondrial fusion.
Conclusions:
- Yeast rhomboid Rbd1p plays a critical role in mitochondrial membrane remodeling through Mgm1p cleavage.
- Intramembrane proteolysis by rhomboids regulates cellular processes beyond signaling.
- Mitochondrial rhomboids are functionally conserved, with the mammalian PARL rescuing yeast mutants.
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