Related Experiment Video
Updated: May 14, 2026
07:03
Isolation of Adipose Tissue Nuclei for Single-Cell Genomic Applications
Published on: June 12, 2020
UCP1 mRNA does not produce heat.
Jan Nedergaard1, Barbara Cannon
1Dept. of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden. jan@metabol.su.se
Biochimica Et Biophysica Acta
|January 29, 2013
Summary
Measuring UCP1 protein levels, not just mRNA, is crucial for accurately assessing the thermogenic capacity of brown and brite/beige adipose tissues in metabolic regulation studies.
Area of Science:
- Metabolic Regulation
- Adipose Tissue Biology
- Thermogenesis
Background:
- Brown adipose tissue (BAT) and UCP1 play roles in metabolic regulation.
- Accurate quantification of thermogenic capacities in brown and brite/beige adipose tissues is of significant interest.
Purpose of the Study:
- To determine the most adequate parameters for quantifying thermogenic capacities of adipose tissues.
- To evaluate the relevance of UCP1 mRNA levels versus UCP1 protein levels for estimating thermogenic capacity.
Main Methods:
- Comparison of UCP1 mRNA levels and total UCP1 protein levels in brown and brite/beige adipose tissues under cold acclimation.
- Correlation of in-vitro measurements with nonshivering thermogenesis.
Main Results:
- UCP1 protein levels, not mRNA, accurately reflect maximal thermogenic capacity and temporal changes in brown adipose tissue.
- Brite/beige adipose tissues show high fold-increases in UCP1 mRNA due to low baseline levels, but their total UCP1 protein and thermogenic capacity are significantly lower than brown adipose tissue.
Conclusions:
- UCP1 protein levels are the most physiologically relevant parameter for assessing thermogenic capacity.
- Relying solely on UCP1 mRNA levels can lead to overestimation of brite/beige adipose tissue significance and inaccurate conclusions about metabolic regulation.
Related Concept Videos
02:27Nonsense-mediated mRNA Decay
The Upf proteins that carry out nonsense-mediated decay (NMD) are found in all eukaryotic organisms, including humans. Each protein has an individual role, but they need to work in collaboration. Upf1 is an ATP-dependent RNA helicase that unwinds the RNA helix. Because Upf1 can unwind any RNA, Upf2 and Upf3 are required to help Upf1 discriminate between nonsense and normal mRNAs.
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
02:27Nonsense-mediated mRNA Decay
The Upf proteins that carry out nonsense-mediated decay (NMD) are found in all eukaryotic organisms, including humans. Each protein has an individual role, but they need to work in collaboration. Upf1 is an ATP-dependent RNA helicase that unwinds the RNA helix. Because Upf1 can unwind any RNA, Upf2 and Upf3 are required to help Upf1 discriminate between nonsense and normal mRNAs.
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
01:31Regulation of the Unfolded Protein Response
Inositol-requiring kinase one or IRE1 is the most conserved eukaryotic unfolded protein response (UPR) receptor. It is a type I transmembrane protein kinase receptor with a distinctive site-specific RNase activity. As the binding mechanics of the misfolded proteins with the N-terminal domain of IRE-1 are unclear, three binding models — direct, indirect, and allosteric -- are proposed for receptor activation. Nevertheless, it is known that once a misfolded protein associates with IRE1, it...
02:31Nuclear Export of mRNA
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
02:31Nuclear Export of mRNA
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
01:37The Unfolded Protein Response
The ER is the hub of protein synthesis in a cell. It has robust systems to quality control protein folding and also for degradation of terminally misfolded proteins. Under normal conditions, a small proportion of misfolded proteins that cannot be salvaged need to be transported to the cytoplasm by the ER-associated degradation or ERAD pathways. However, if the ERAD cannot handle the misfolded proteins, the cell activates the unfolded protein response or UPR to adjust the protein folding...