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Updated: Jan 5, 2026
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High-resolution Respirometry to Measure Mitochondrial Function of Intact Beta Cells in the Presence of Natural Compounds
Published on: January 23, 2018
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RNA binding protein HuD contributes to β-cell dysfunction by impairing mitochondria dynamics
Youlim Hong1, Hyosun Tak1, Chongtae Kim1,2
1Department of Biochemistry, The Catholic University of Korea College of Medicine, Seoul, 06591, South Korea.
Cell Death and Differentiation
|October 30, 2019
Summary
RNA binding protein HuD regulates mitochondrial fusion in pancreatic beta-cells. Reduced HuD levels cause mitochondrial fragmentation and dysfunction, impacting diabetes pathology.
Area of Science:
- Cell Biology
- Endocrinology
- Molecular Biology
Background:
- Mitochondrial dynamics are crucial for pancreatic beta-cell function.
- Imbalances in mitochondrial dynamics contribute to diabetes.
- The role of RNA binding protein HuD in beta-cell mitochondrial health is unclear.
Purpose of the Study:
- To investigate the role of RNA binding protein HuD in regulating mitochondrial dynamics in pancreatic beta-cells.
- To elucidate the molecular mechanisms by which HuD influences mitochondrial health in the context of diabetes.
Main Methods:
- Utilized db/db mice and HuD knockout (KO) mice to study mitochondrial morphology.
- Assessed mitochondrial activity using mitochondrial membrane potential and ATP production in mouse insulinoma betaTC6 cells.
- Investigated the binding of HuD to mitofusin 2 (Mfn2) mRNA using molecular biology techniques.
Main Results:
- HuD deficiency led to increased mitochondrial fragmentation in pancreatic tissues.
- Downregulation of HuD in betaTC6 cells resulted in fragmented mitochondria and reduced mitochondrial activity.
- HuD directly binds to the 3'-untranslated region of Mfn2 mRNA, promoting its expression.
- Restoring Mfn2 levels in HuD-deficient cells ameliorated mitochondrial dysfunction.
Conclusions:
- HuD plays a novel role in promoting mitochondrial fusion in pancreatic beta-cells.
- HuD regulates mitochondrial dynamics through the Mfn2 pathway.
- Reduced HuD expression contributes to beta-cell dysfunction in diabetes via Mfn2-mediated mitochondrial impairment.
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