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The unfolded protein response in nutrient sensing and differentiation
Randal J Kaufman1, Donalyn Scheuner, Martin Schröder
1Department of Biological Chemistry, University of Michigan Medical Center, 1150 West Medical Center Drive, Ann Arbor, Michigan 48109-0650, USA. kaufmanr@umich.edu
Nature Reviews. Molecular Cell Biology
|June 4, 2002
Summary
Cells manage protein folding by linking endoplasmic reticulum reactions to nuclear gene expression and cytoplasmic translation. The unfolded protein response pathway balances protein synthesis with cellular energy and nutrient levels for survival and specialized cell functions.
Area of Science:
- Cellular Biology
- Molecular Biology
- Biochemistry
Background:
- Eukaryotic cells integrate protein folding in the endoplasmic reticulum with nuclear gene expression and cytoplasmic translation.
- Increased protein synthesis can impair proper protein folding, necessitating cellular regulatory mechanisms.
- The unfolded protein response (UPR) is a critical signal-transduction pathway that manages these processes.
Purpose of the Study:
- To investigate the role of the unfolded protein response (UPR) in coordinating cellular processes.
- To explore how UPR pathways link protein synthesis rates with nutrient and energy availability.
- To understand the regulation of cell differentiation by UPR under nutrient-limiting conditions.
Main Methods:
- Analysis of signal-transduction pathways controlling transcription and translation.
- Investigating the coordination between protein synthesis rates and cellular energy stores.
- Studying the regulation of cell differentiation in response to nutrient availability.
Main Results:
- UPR pathways are crucial for coordinating protein folding, gene expression, and translation.
- These pathways dynamically adjust protein synthesis based on nutrient and energy levels.
- UPR actively regulates cell differentiation for survival and production of secreted proteins.
Conclusions:
- The unfolded protein response is a central regulator of cellular homeostasis and adaptation.
- UPR ensures proper protein folding and cellular function under varying metabolic conditions.
- UPR plays a key role in cell differentiation, enabling survival and specialized secretory functions.
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