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Published on: May 7, 2013
Endoplasmicreticulum-induced signal transduction and gene expression
1The Institute for Experimental Cancer Research, Tumor Biology Center, PO Box 1120, D-79106 Freiburg, Germany.
Trends in Cell Biology
|February 1, 1997
Summary
Cells activate three distinct endoplasmic reticulum (ER) pathways to the nucleus in response to unfolded proteins, membrane protein overload, or sterol depletion. This review details these crucial cellular stress responses.
Area of Science:
- Cellular Biology
- Molecular Biology
- Biochemistry
Background:
- The endoplasmic reticulum (ER) is vital for protein and lipid homeostasis.
- Cells possess sophisticated mechanisms to maintain ER function under stress.
- Perturbations in ER function trigger specific signaling pathways.
Purpose of the Study:
- To review the known signal-transduction pathways originating from the ER.
- To summarize the molecular mechanisms of three distinct ER-nucleus signaling pathways.
- To provide an overview of cellular responses to ER stress.
Main Methods:
- Literature review of studies on ER stress response pathways.
- Analysis of signal transduction mechanisms.
- Summary of transcription factor activation and nuclear translocation.
Main Results:
- Three distinct ER-nucleus pathways are identified: unfolded protein response, membrane protein overload response, and sterol depletion response.
- Each pathway is activated by a specific cellular stress signal.
- These pathways culminate in nuclear events, including transcription factor translocation.
Conclusions:
- The ER communicates with the nucleus through at least three distinct signaling pathways.
- Understanding these pathways is crucial for comprehending cellular adaptation to stress.
- Further research can elucidate therapeutic targets for ER-related diseases.
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