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Published on: January 26, 2015
Regulated secretion of conventional lysosomes
1Section of Microbial Pathogenesis, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, CT 06536, USA. norma.andrews@yale.edu
Trends in Cell Biology
|July 8, 2000
Summary
Conventional lysosomes, not just specialized cells, can release contents via calcium-triggered membrane fusion. This reveals lysosomes have a more active role in cellular processes than previously understood.
Area of Science:
- Cell Biology
- Molecular Biology
- Physiology
Background:
- Regulated secretion was historically considered exclusive to specialized cell types.
- Secretory lysosomes in hematopoietic cells were seen as uniquely adapted for regulated exocytosis.
Purpose of the Study:
- To investigate the exocytotic capabilities of conventional lysosomes.
- To challenge the traditional view of lysosomes as solely end-stage organelles.
Main Methods:
- Analysis of cellular responses to increased intracellular calcium (Ca2+).
- Observation of lysosome-plasma membrane fusion events in various cell types.
Main Results:
- Evidence suggests conventional lysosomes can undergo regulated exocytosis.
- Lysosomal fusion with the plasma membrane is triggered by intracellular Ca2+ surges.
Conclusions:
- Lysosomes possess an active, previously unrecognized role in regulated secretion.
- The traditional model of lysosomes as a 'final' destination in the endocytic pathway is incomplete.
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