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Updated: Jan 9, 2026
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Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess
Published on: June 1, 2022
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Tom70-mediated mitochondria-nuclear envelope contacts regulate nuclear pore complex inheritance during gametogenesis.
Cyrus T Ruediger1, Benjamin S Styler1, Eric M Sawyer1,2
1Department of Molecular and Cell Biology, University of California, Berkeley, CA, 94720, USA.
Biorxiv : the Preprint Server for Biology
|December 3, 2025
Summary
Gametogenesis relies on the mitochondrial protein Tom70 to exclude unwanted nuclear components from developing gametes. This process ensures cellular lineage rejuvenation and safeguards gamete integrity through organelle contact. Keywords: gametogenesis, Tom70, nuclear exclusion, gamete integrity, organelle contact.
Area of Science:
- Cell Biology
- Genetics
- Molecular Biology
Background:
- Gametogenesis rejuvenates cellular lineages by excluding senescence factors from gametes.
- In yeast, this involves the Gametogenesis-Uninherited Nuclear Compartment (GUNC) for exclusion.
- Nuclear quality control is crucial for maintaining gamete integrity.
Purpose of the Study:
- To identify key regulators of GUNC-mediated exclusion during gametogenesis.
- To elucidate the role of mitochondrial proteins in nuclear quality control.
- To understand the mechanisms of selective nuclear inheritance.
Main Methods:
- Genetic analysis of Saccharomyces cerevisiae mutants.
- Microscopy to visualize nuclear and mitochondrial components.
- Investigating protein interactions and localization during meiosis.
Main Results:
- The mitochondrial import receptor Tom70 is identified as a regulator of GUNC.
- Loss of TOM70 disrupts the sequestration of nuclear pore complexes into the GUNC.
- Tom70 mediates mitochondria-nuclear envelope tethering, recruiting Cnm1 during meiosis II.
Conclusions:
- Tom70 plays a meiosis-specific role in mitochondria-nuclear envelope tethering for GUNC function.
- Organelle contact-dependent pathways remodel the nuclear envelope for selective nuclear inheritance.
- This study reveals a novel pathway for safeguarding gamete integrity through integrated organelle contacts and nuclear quality control.
Keywords:
Cnm1Tom70gametogenesismeiosismembrane contactmitochondrianuclear pore complexorganelle tetherquality controlMore Related Videos
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