The proline cycle as an eukaryotic redox valve.
Yao Zheng1, Cécile Cabassa-Hourton1, Séverine Planchais1
1Sorbonne Université, UPEC, CNRS, IRD, INRAE, Institute of Ecology and Environmental Sciences of Paris (iEES), F-75005 Paris, France.
Journal of Experimental Botany
|July 31, 2021
Summary
The proline cycle, beyond accumulating proline, actively manages cellular redox balance and energy status by shuttling reducing power between cellular compartments, particularly between the cytosol and mitochondria in plants.
Area of Science:
- Biochemistry
- Plant Physiology
- Cellular Metabolism
Background:
- Proline is a known protein component and osmolyte.
- Emerging research highlights proline's roles in redox balance and energy regulation.
- The proline cycle facilitates proline accumulation and redox shuttling between cytosol and mitochondria.
Purpose of the Study:
- To review recent evidence on the proline cycle's regulation of redox status.
- To explore the proline cycle's interaction with other redox shuttles.
- To examine the spatial and regulatory roles of the proline cycle in plants.
Main Methods:
- Literature review of recent studies on the proline cycle.
- Analysis of proline-glutamate interconversion and redox power transfer.
- Consideration of proline transport and metabolic regimes in different plant organs.
Main Results:
- The proline cycle significantly impacts cellular redox status beyond proline levels.
- Interconversion between proline and glutamate effectively shuttles reducing power.
- Proline transport between organs with distinct metabolic states is crucial.
Conclusions:
- The proline cycle is vital for regulating plant energy and redox power.
- Intricate coordination between mitochondria and cytosol is key to proline's function.
- Understanding the proline cycle offers insights into plant stress response and metabolism.
Keywords:
Mitochondriaproline cycleproline metabolismproline transportredox shuttleredox statusredox valveMore Related Videos
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