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The endolysosomal system in conventional and unconventional protein secretion
Eloïse Néel1, Marioara Chiritoiu-Butnaru2, William Fargues1
1Institute of Functional Genomics, University of Montpellier, CNRS, INSERM , Montpellier, France.
Unconventional protein secretion utilizes alternative pathways beyond the endoplasmic reticulum-Golgi apparatus. Lysosomes play a key role in this process, facilitating the export of cytosolic proteins via lysosomal transport and exocytosis.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- The conventional secretory pathway involves the endoplasmic reticulum and Golgi apparatus for protein export.
- Emerging evidence highlights unconventional protein secretion (UPS) routes for cytosolic proteins.
- Lysosomes are central organelles involved in various cellular trafficking pathways.
Purpose of the Study:
- To explore the role of lysosomes in unconventional protein secretion.
- To elucidate the mechanisms of lysosomal transport and exocytosis in UPS.
- To understand the physiological significance of lysosome-mediated UPS.
Main Methods:
- Investigating protein trafficking pathways using advanced microscopy techniques.
- Analyzing lysosomal function and dynamics in response to cellular signals.
- Employing biochemical assays to identify cargo proteins and associated factors in UPS.
Main Results:
- Lysosomes are confirmed as key players in unconventional protein secretion.
- Lysosomal exocytosis facilitates the release of specific cytosolic proteins.
- This pathway is crucial for various physiological processes and cellular responses.
Conclusions:
- Lysosomes are versatile organelles involved in both conventional and unconventional protein secretion.
- Lysosomal transport and exocytosis represent a significant mechanism for UPS.
- Understanding lysosome-mediated UPS offers new insights into cellular communication and homeostasis.
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