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Homogeneous Time-resolved Förster Resonance Energy Transfer-based Assay for Detection of Insulin Secretion
Published on: May 10, 2018
Protein markers for insulin-producing beta cells with higher glucose sensitivity
Geert A Martens1, Lei Jiang, Katrijn Verhaeghen
1Diabetes Research Center, Brussels Free University (VUB), Brussels, Belgium. geert.martens@vub.ac.be
Plos One
|December 15, 2010
Summary
Differences in pancreatic beta cell glucose sensitivity are linked to higher levels of glycolytic enzymes, not mitochondrial ones. This proteomic study identifies key protein markers for beta cell function and insulin production variations.
Area of Science:
- * Proteomics
- * Cellular metabolism
- * Endocrinology
Background:
- * Pancreatic beta cells exhibit varying glucose sensitivity and insulin production.
- * Identifying protein markers can elucidate these functional differences.
Purpose of the Study:
- * To identify protein markers associated with functional glucose sensitivity variations in rat beta cells.
- * To characterize the proteome of beta cell subpopulations with differing metabolic responsiveness.
Main Methods:
- * Flow-sorting of rat beta cell subpopulations based on glucose-induced NAD(P)H levels.
- * Label-free data-independent alternate scanning liquid chromatography-mass spectrometry (LC-MS) for proteome quantification.
- * Comparative proteomic analysis with other tissues and cell types for beta cell-selective protein identification.
Main Results:
- * 943 proteins were quantified across all tissues; 93 were unique to beta cells.
- * Beta cells with high glucose responsiveness showed 50% higher expression of protein biosynthesis regulators.
- * These responsive beta cells also had 50% higher levels of glycolytic enzymes and cytosolic malate/aspartate-NADH-shuttle components.
Conclusions:
- * Subtle proteomic variations correlate with beta cell metabolic glucose responsiveness.
- * Increased glycolytic enzyme levels, not mitochondrial enzymes, characterize metabolically responsive beta cells.
- * Findings provide insights into the molecular basis of beta cell functional heterogeneity.
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