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Updated: Jun 6, 2026
05:58
Measuring Relative Insulin Secretion using a Co-Secreted Luciferase Surrogate
Published on: June 25, 2019
Pim3 negatively regulates glucose-stimulated insulin secretion
Gregory Vlacich1, Martijn C Nawijn, Gene C Webb
1Department of Medicine, University of Chicago, Chicago, IL, USA.
Islets
|November 25, 2010
Summary
The study identifies Pim3 as a novel gene that regulates pancreatic beta-cell function. Lowering Pim3 enhances insulin secretion and improves glucose tolerance, suggesting a role in glucose homeostasis.
Area of Science:
- Endocrinology
- Molecular Biology
- Metabolism
Background:
- Pancreatic beta-cell function is crucial for glucose homeostasis, regulated by complex signaling pathways.
- Novel signaling intermediates in beta-cells remain to be fully characterized.
Purpose of the Study:
- To identify and characterize novel signaling intermediates regulating beta-cell function.
- To investigate the role of Pim3 in glucose-stimulated insulin secretion and glucose tolerance.
Main Methods:
- Microarray analysis of glucose-stimulated murine insulinoma (MIN6) cells.
- Analysis of Pim3 expression in murine pancreas and isolated islets.
- Assessment of insulin secretion in MIN6 cells and Pim3 knockout (Pim3-/-) mouse islets.
- In vivo glucose tolerance tests in Pim3-/- mice.
- Analysis of ERK1/2 phosphorylation and interaction with SOCS6.
Main Results:
- Pim3 is a glucose-responsive gene transiently induced in pancreatic beta-cells.
- Perturbation of Pim3 function enhanced glucose-stimulated insulin secretion and improved glucose tolerance in Pim3-/- mice.
- Pim3 deficiency led to increased ERK1/2 phosphorylation and reduced SOCS6 levels, indicating Pim3 negatively regulates ERK1/2 activity via SOCS6.
- Pim3-/- mice exhibited increased insulin sensitivity.
Conclusions:
- Pim3 is a novel negative regulator of insulin secretion and plays a role in glucose homeostasis.
- Pim3 regulates beta-cell function by inhibiting ERK1/2 activation through SOCS6.
- Targeting Pim3 may offer therapeutic potential for metabolic disorders.
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