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Updated: Jun 14, 2026
16:01
Investigating Mast Cell Secretory Granules; from Biosynthesis to Exocytosis
Published on: January 26, 2015
Cell secretion mediated by granule-associated vesicle transport: a glimpse at evolution
Enrico Crivellato1, Beatrice Nico, Valentina Patrizia Gallo
1Department of Medical and Morphological Research, Section of Anatomy, University of Udine School of Medicine, Udine, Italy. enrico.crivellato@uniud.it
Anatomical Record (Hoboken, N.J. : 2007)
|March 27, 2010
Summary
Piecemeal degranulation (PMD) is a regulated secretion pathway found in vertebrates, mobilizing specific cell products. This review explores its evolutionary history and potential origins in early animals.
Area of Science:
- Cell Biology
- Evolutionary Biology
- Biochemistry
Background:
- Regulated secretion is fundamental for cell function, observed across eukaryotic evolution.
- Piecemeal degranulation (PMD) is a specialized, vesicle-mediated secretion pathway.
- PMD was first identified in inflammatory and endocrine cells.
Purpose of the Study:
- To trace the evolutionary history of piecemeal degranulation (PMD).
- To review current understanding and implications of PMD.
- To explore the potential origins and significance of PMD in invertebrates.
Main Methods:
- Literature review of existing studies on regulated secretion and PMD.
- Analysis of experimental data and theoretical implications of vesicle-mediated degranulation.
- Comparative analysis of secretory patterns across different species.
Main Results:
- PMD mobilizes specific aliquots of granule-associated material for targeted transport.
- This secretion pattern is well-documented in various vertebrate classes.
- No data currently exists for PMD in invertebrates, suggesting a potential evolutionary gap.
Conclusions:
- PMD is a conserved regulated secretion mechanism with potential ancient origins.
- The evolutionary emergence of PMD may coincide with the appearance of early metazoans.
- Further investigation is needed to confirm PMD in invertebrates and elucidate its biological significance.
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