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Endomembrane-Based Signaling by GPCRs and G-Proteins
Federica Liccardo1, Alberto Luini2, Rosaria Di Martino2
1Cardiovascular Research Institute, University of California San Francisco (UCSF), 555 Mission Bay Blvd., San Francisco, CA 94158, USA.
Cells
|February 15, 2022
Summary
G-protein-coupled receptors (GPCRs) and G-proteins are key signaling proteins. Recent findings show GPCRs and G-proteins function within endomembranes, influencing cellular pathways and organelle function.
Area of Science:
- Cellular Biology
- Molecular Signaling
Background:
- G-protein-coupled receptors (GPCRs) and G-proteins are crucial signaling molecules involved in numerous physiological and pathological processes.
- Traditionally, GPCR signaling was believed to occur exclusively at the plasma membrane.
Purpose of the Study:
- To review the general roles and classification of GPCRs and G-proteins.
- To focus on the signaling pathways of GPCRs and G-proteins within the endomembrane system, particularly the membrane transport apparatus.
Main Methods:
- Literature review of existing research on GPCR and G-protein signaling.
- Analysis of evidence supporting intracellular localization and function of GPCRs and G-proteins.
Main Results:
- GPCRs and G-proteins are now known to reside on endomembranes, not just the plasma membrane.
- These intracellular receptors can initiate or propagate signaling pathways through the secretory route organelles.
Conclusions:
- The intracellular signaling roles of GPCRs and G-proteins within endomembranes are critical for cellular function.
- Further investigation is needed to fully understand how these alternative pathways impact physiological and pathological functions of endomembranes.
Keywords:
G-proteinGPCRGolgi apparatusendomembrane signalingendosomesnuclear signalingsecretory pathwayMore Related Videos
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