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Updated: Sep 10, 2025
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Confocal Imaging of Neuropeptide Y-pHluorin: A Technique to Visualize Insulin Granule Exocytosis in Intact Murine and Human Islets
Published on: September 13, 2017
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Secretory stimuli distinctly regulate insulin secretory granule maturation through structural remodeling
Aneesh Deshmukh1, Kevin Chang1, Janielle Cuala2
1Department of Chemistry, Bridge Institute, Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA 90089, USA.
Structure (London, England : 1993)
|August 27, 2025
Summary
Secretory stimuli promote insulin secretory granule (ISG) maturation and cellular reorganization. Understanding how these stimuli affect ISG structure and location offers insights into diabetes and obesity therapies.
Area of Science:
- Cell biology
- Endocrinology
- Metabolic research
Background:
- Insulin secretory granule (ISG) maturation is vital for insulin secretion and glucose homeostasis.
- The regulation of ISG maturation and its response to stimuli are not fully understood.
Purpose of the Study:
- To investigate how secretory stimuli influence ISG maturity and subcellular localization.
- To quantitatively map ISG morphology, density, and location in response to various stimuli.
Main Methods:
- Soft X-ray tomography (SXT) was employed to analyze ISGs in INS-1E and mouse pancreatic beta cells.
- Quantitative mapping of ISG morphology, density, and cellular distribution was performed.
Main Results:
- Activation of glucokinase (GK), GIPR, GLP-1R, and GPR40 promotes ISG maturation.
- Each stimulus induced unique ISG structural remodeling (size, density) via specific signaling pathways.
- Mobilization and redistribution of ISG subpopulations altered cellular organization.
Conclusions:
- Secretory stimuli dynamically regulate ISG maturation and cellular structure.
- Findings provide insights into how current diabetes/obesity therapies affect ISG maturation.
- This research may guide the development of novel, targeted maturation therapies.
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