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Updated: Sep 6, 2025
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Specific Labeling of Mitochondrial Nucleoids for Time-lapse Structured Illumination Microscopy
Published on: June 4, 2020
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Evidence for mitochondrial Lonp1 expression in the nucleus
Lara Gibellini1, Rebecca Borella1, Anna De Gaetano2
1Department of Medical and Surgical Sciences for Children and Adults, University of Modena and Reggio Emilia, Modena, Italy.
Scientific Reports
|June 27, 2022
Summary
Mitochondrial protease Lonp1 is also found in the nucleus, where it interacts with heat shock factor 1 (HSF1) to regulate the heat shock (HS) response. This reveals a new extramitochondrial role for Lonp1 in cellular stress.
Area of Science:
- Cell Biology
- Molecular Biology
- Mitochondrial Dynamics
Background:
- Mitochondria-nucleus communication is vital for cellular function but poorly understood.
- The protease Lonp1 was traditionally considered exclusively mitochondrial, impacting morphology, mtDNA, and metabolism.
- Recent findings indicate a significant nuclear presence of Lonp1.
Purpose of the Study:
- To investigate the novel extramitochondrial role of Lonp1.
- To explore the function of nuclear Lonp1 in cellular stress responses.
Main Methods:
- Cellular fractionation to detect Lonp1 localization.
- Analysis of Lonp1 nuclear import under varying conditions, including heat shock.
- Co-immunoprecipitation to identify nuclear Lonp1 interacting partners.
Main Results:
- Up to 22% of cellular Lonp1 was detected in the nucleus.
- Nuclear Lonp1 levels are modulated by heat shock (HS).
- Nuclear Lonp1 interacts with heat shock factor 1 (HSF1) and influences the HS response.
Conclusions:
- Lonp1 possesses a previously unrecognized extramitochondrial function.
- Nuclear Lonp1 plays a role in the cellular response to stress, specifically heat shock.
- These findings expand our understanding of mitochondrial protein function and cellular signaling pathways.
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