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Updated: May 31, 2026
10:36
Measurements of Physiological Stress Responses in C. Elegans
Published on: May 21, 2020
An evolutionarily conserved Rit GTPase-p38 MAPK signaling pathway mediates oxidative stress resistance.
Weikang Cai1, Jennifer L Rudolph, Susan M W Harrison
1Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536-0509, USA.
Molecular Biology of the Cell
|July 9, 2011
Summary
Rit GTPases are crucial for cell survival during oxidative stress. These proteins regulate a conserved p38 MAPK signaling pathway, essential for protecting cells from reactive oxygen species (ROS) damage.
Area of Science:
- Cellular Biology
- Molecular Biology
- Genetics
Background:
- Ras-related small GTP-binding proteins regulate diverse cellular processes via effector pathways, notably mitogen-activated protein kinase (MAPK) cascades.
- The physiological functions of the Rit/Rin subfamily of Ras GTPases remain largely undefined.
- Understanding these functions is critical for elucidating cellular stress response mechanisms.
Purpose of the Study:
- To investigate the physiological role of Rit subfamily GTPases in cellular survival.
- To determine if Rit GTPases are involved in response to oxidative stress.
- To elucidate the signaling pathways regulated by Rit GTPases during stress.
Main Methods:
- Utilized knockout mouse models and Drosophila melanogaster to study Rit subfamily GTPase function.
- Analyzed primary embryonic fibroblasts from Rit knockout mice for apoptosis and signaling pathway disruptions.
- Assessed stress susceptibility and p38 signaling in Drosophila melanogaster lacking D-RIC.
Main Results:
- Rit knockout mice fibroblasts showed increased apoptosis and disrupted MAPK signaling upon reactive oxygen species (ROS) exposure.
- This disruption specifically affected the p38-MK2-HSP27 cascade, impacting Akt activation and Bad phosphorylation.
- Drosophila melanogaster lacking D-RIC exhibited heightened susceptibility to environmental stresses and reduced stress-induced p38 signaling.
Conclusions:
- Established an evolutionarily conserved role for Rit GTPases in governing cell survival against oxidative stress.
- Demonstrated that Rit GTPases are critical regulators of a p38 MAPK-dependent signaling cascade.
- Identified this pathway as a key survival mechanism for cells encountering ROS-induced damage.
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