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Post-Translational Modification of Cysteines: A Key Determinant of Endoplasmic Reticulum-Mitochondria Contacts
Arthur Bassot1, Junsheng Chen1, Thomas Simmen1
1Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada.
Contact (Thousand Oaks (Ventura County, Calif.))
|June 27, 2023
Summary
Cells adapt to environmental changes by modifying proteins using cysteine post-translational modifications (PTMs), particularly near mitochondria-endoplasmic reticulum contacts (MERCs). These PTMs regulate cell function and are implicated in diseases like cancer.
Area of Science:
- Cellular Biology
- Biochemistry
- Physiology
Background:
- Cells require redox homeostasis to maintain function.
- Cysteine post-translational modifications (PTMs) are key to adapting protein function.
- Mitochondria-Endoplasmic Reticulum Contacts (MERCs) are crucial for inter-organelle communication and metabolic control.
Purpose of the Study:
- To investigate the role of PTMs at MERCs in cellular redox adaptation.
- To understand how reactive oxygen species (ROS) influence MERC function via protein PTMs.
- To explore the link between altered PTMs at MERCs and human diseases.
Main Methods:
- Analysis of protein modifications at mitochondria-associated membranes (MAMs).
- Investigating the impact of ROS on MERC-associated protein function.
- Correlating PTM patterns with cellular homeostasis and disease states.
Main Results:
- PTMs of proteins at MERCs are critical for adapting to redox changes.
- ROS-induced PTMs at MERCs modulate Ca2+ fluxes and lipid exchange.
- Dysregulation of PTMs at MERCs is linked to physiological processes and diseases, including cancer and neurodegeneration.
Conclusions:
- Cysteine PTMs at MERCs are essential for cellular redox adaptation and homeostasis.
- MERCs act as signaling hubs where ROS-mediated PTMs fine-tune inter-organelle communication.
- Aberrant PTMs at MERCs represent a potential mechanism underlying various human pathologies.
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