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Updated: Jun 26, 2026
09:41
Measuring the Rate of Lipolysis in Ex Vivo Murine Adipose Tissue and Primary Preadipocytes Differentiated In Vitro
Published on: March 17, 2023
TgI4 lipase: a big fat target for cell-cycle entry
1Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY 11794-5222, USA. bfutcher@ms.cc.sunysb.edu
Molecular Cell
|February 4, 2009
Summary
Quiescent yeast re-enter the cell cycle by activating a lipase enzyme. This enzyme breaks down fat into fatty acids, fueling cell cycle progression.
Area of Science:
- Cell biology
- Biochemistry
- Molecular genetics
Background:
- Yeast cell cycle regulation is crucial for understanding eukaryotic cell proliferation.
- Quiescence represents a dormant state cells enter under unfavorable conditions.
- Re-entry into the cell cycle requires precise molecular signaling pathways.
Discussion:
- The study identifies a novel role for the lipase TgI4 in cell cycle re-entry.
- Activation of TgI4 by cyclin-dependent kinase (CDK) links cell cycle machinery to metabolic processes.
- Lipid metabolism is shown to be a critical source of energy for cell division.
Key Insights:
- Phosphorylation and activation of lipase TgI4 by CDK initiates fat breakdown.
- Fatty acids released by TgI4 serve as essential substrates for cell cycle entry.
- This mechanism highlights a direct link between lipid catabolism and cell cycle progression in yeast.
Outlook:
- Further research could explore similar mechanisms in other quiescent cell types.
- Understanding this pathway may offer targets for modulating cell proliferation in various contexts.
- Investigating the specific fatty acids utilized could reveal metabolic fine-tuning of cell cycle entry.
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