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Visualization of G3BP Stress Granules Dynamics in Live Primary Cells
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ER stress signaling requires RHD3, a functionally conserved ER-shaping GTPase
Ya-Shiuan Lai1, Giovanni Stefano1, Federica Brandizzi2
1MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI 48824, USA Department of Plant Biology, Michigan State University, East Lansing, MI 48824, USA.
Journal of Cell Science
|May 31, 2014
Summary
The endoplasmic reticulum (ER) protein RHD3 is crucial for cell biology. Loss of RHD3 disrupts the unfolded protein response (UPR) by interfering with IRE1 mRNA splicing, impacting ER signaling.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- The relationship between organelle structure and function is a key question in cell biology.
- The unfolded protein response (UPR) is an essential signaling pathway within the endoplasmic reticulum (ER).
Purpose of the Study:
- To investigate the impact of defective ER structure on the UPR in Arabidopsis.
- To determine the role of the ER-shaping GTPase Root Hair Defective 3 (RHD3) in ER signaling.
Main Methods:
- Utilized molecular and genetic approaches in Arabidopsis.
- Assessed the ability of ER structure mutants to invoke the UPR.
- Investigated the interaction between RHD3 and the UPR master regulator IRE1.
Main Results:
- Mutants with defective ER structure were analyzed for UPR activation.
- Loss of RHD3 was found to specifically disrupt the UPR.
- RHD3 disruption interferes with the mRNA splicing function of IRE1.
Conclusions:
- RHD3 plays a novel role in the endoplasmic reticulum.
- ER-shaping mutations have specific effects on ER function.
- RHD3 is essential for proper UPR signaling by modulating IRE1 activity.
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