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Visualization of Endoplasmic Reticulum Localized mRNAs in Mammalian Cells
Published on: December 17, 2012
Message on the web: mRNA and ER co-trafficking.
1Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel. jeffrey.gerst@weizmann.ac.il
Trends in Cell Biology
|January 25, 2008
Summary
Cytosolic messenger RNAs (mRNAs) associate with the endoplasmic reticulum (ER) network in various cells. This association may regulate protein synthesis at specific cellular locations, impacting growth and response to stimuli.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Messenger RNAs (mRNAs) encoding secreted and membrane proteins are targeted to the endoplasmic reticulum (ER) for translocation.
- Unexpectedly, mRNAs for cytosolic proteins also associate with ER membranes in diverse eukaryotic organisms.
- This association occurs with the cortical ER (cER) network, extending to the plasma membrane.
Purpose of the Study:
- To investigate the association of cytosolic mRNAs with the cortical ER (cER) network.
- To understand the functional implications of cER-mRNA interactions in cellular processes.
Main Methods:
- Microscopy techniques to visualize mRNA localization.
- Biochemical assays to confirm mRNA-ER association.
- Genetic manipulation to study the role of cER-mRNA interactions.
Main Results:
- Cytosolic mRNAs were observed to associate with the cER network in yeast, plants, and animal cells.
- This physical association allows for cytoskeleton-mediated co-trafficking and anchoring of cER-mRNA.
- The cER-mRNA complex links mRNA localization to cellular structures involved in growth and response.
Conclusions:
- The association of cytosolic mRNAs with the cER network is a conserved eukaryotic feature.
- This interaction potentially regulates protein synthesis spatially, particularly at sites of polarized growth or in response to stimuli.
- cER-mRNA interactions may play roles in cell division, synaptic remodeling, and neuronal injury responses.
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