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Measuring the Rate of Lipolysis in Ex Vivo Murine Adipose Tissue and Primary Preadipocytes Differentiated In Vitro
Published on: March 17, 2023
Polymerase I and transcript release factor regulates lipolysis via a phosphorylation-dependent mechanism
Nabila Aboulaich1, Patricia C Chui, John M Asara
1Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA.
Diabetes
|February 2, 2011
Summary
Polymerase I and transcript release factor (PTRF) mediates fat mobilization in adipose tissue. Its phosphorylation is crucial for efficient lipid mobilization, highlighting a novel role in lipolysis.
Area of Science:
- Biochemistry
- Cell Biology
- Endocrinology
Background:
- Polymerase I and transcript release factor (PTRF) is highly expressed in adipose tissue.
- PTRF is an integral structural component of caveolae.
- A novel role for PTRF in lipid mobilization is investigated.
Purpose of the Study:
- To elucidate the function of PTRF in adipose tissue.
- To determine the role of PTRF in lipid mobilization and lipolysis.
- To investigate the impact of PTRF phosphorylation on fat mobilization.
Main Methods:
- PTRF expression analysis in mouse adipose depots under different nutritional and hormonal conditions.
- Lipolysis studies using PTRF knockdown and overexpression in 3T3-L1 adipocytes.
- Analysis of PTRF phosphorylation sites and their impact on lipolysis.
Main Results:
- PTRF expression in white adipose tissue (WAT) is regulated by fasting, refeeding, insulin, and isoproterenol.
- PTRF knockdown attenuated, while overexpression enhanced, isoproterenol-stimulated glycerol release.
- Mutation of PTRF phosphorylation sites reduced lipolysis, indicating phosphorylation is necessary.
Conclusions:
- PTRF has a novel adipose tissue-specific function as a mediator of lipolysis.
- Phosphorylation of PTRF is essential for efficient fat mobilization.
- PTRF plays a critical role in regulating lipid metabolism in adipocytes.
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