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Outer mitochondrial membrane E3 Ub ligase MARCH5 controls mitochondrial steps in peroxisome biogenesis

Nicolas Verhoeven, Yumiko Oshima, Etienne Cartier

    Biorxiv : the Preprint Server for Biology
    |September 11, 2023
    PubMed

    Insights

    Mitochondrial E3 Ub ligase MARCH5 is essential for creating new peroxisomes from mitochondria. Its absence halts peroxisome development, supporting a hybrid model of organelle biogenesis.

    Area of Science:

    • Cell Biology
    • Organelle Biogenesis
    • Mitochondrial Dynamics

    Background:

    • Peroxisome de novo biogenesis is a complex process requiring mitochondrial contributions.
    • The precise mitochondrial proteins involved in initiating peroxisome formation remain largely unidentified.
    • Understanding these mitochondrial factors is crucial for elucidating peroxisome biogenesis pathways.

    Approach:

    • Investigated the role of the outer mitochondrial membrane (OMM)-associated E3 Ub ligase MARCH5 in peroxisome biogenesis.
    • Utilized MARCH5 knockout and activity-deficient mutants to assess its function.
    • Examined the impact of MARCH5 depletion on peroxisome formation, protein expression, and localization, including interactions with Pex14 and Tom20.

    Key Points:

    • MARCH5 is vital for generating mitochondria-derived pre-peroxisomes, controlling their maturation.
    • MARCH5 knockout leads to immature peroxisomes and reduced expression of peroxisomal proteins.
    • MARCH5 acts upstream of Pex14 in the mitochondrial phase of peroxisome biogenesis.

    Conclusions:

    • MARCH5 is an essential mitochondrial protein that initiates peroxisome biogenesis.
    • The findings validate the hybrid, mitochondria-dependent model of peroxisome biogenesis.
    • MARCH5's role highlights a critical link between mitochondrial function and peroxisome formation.

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