Related Experiment Video
Updated: Nov 6, 2025
08:01
Measurement of Insulin- and Contraction-Stimulated Glucose Uptake in Isolated and Incubated Mature Skeletal Muscle from Mice
Published on: May 16, 2021
6.2K
Tmod3 Phosphorylation Mediates AMPK-Dependent GLUT4 Plasma Membrane Insertion in Myoblasts
Man Mohan Shrestha1, Chun-Yan Lim1, Xuezhi Bi2
1Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, Agency for Science, Technology and Research (ASTAR), Singapore, Singapore.
Frontiers in Endocrinology
|May 7, 2021
Summary
Tropomodulin 3 (Tmod3) is identified as a novel AMPK effector that mediates glucose uptake in muscle cells. Tmod3 regulates glucose transporter 4 (GLUT4) translocation and insertion into the plasma membrane, crucial for muscle glucose homeostasis.
Area of Science:
- Muscle physiology
- Cellular metabolism
- Molecular biology
Background:
- Insulin and muscle contractions stimulate glucose uptake in skeletal muscles by promoting glucose transporter 4 (GLUT4) translocation to the plasma membrane.
- AMP-activated protein kinase (AMPK) activation during muscle contraction enhances GLUT4 translocation, but its direct effectors remain largely unknown.
Purpose of the Study:
- To identify novel AMPK effectors involved in regulating GLUT4 translocation.
- To elucidate the role of these effectors in AMPK-dependent glucose uptake in muscle cells.
Main Methods:
- Biochemical assays
- Molecular biology techniques
- Fluorescent microscopy imaging
- Gain- and loss-of-function mutants of tropomodulin 3 (Tmod3) were utilized.
Main Results:
- Tropomodulin 3 (Tmod3) was identified as a novel AMPK substrate.
- Tmod3 acts as a crucial mediator of AMPK-dependent GLUT4 translocation and glucose uptake in myoblasts.
- Tmod3 is essential for AMPK-induced F-actin remodeling and GLUT4 insertion into the plasma membrane.
Conclusions:
- Tmod3 is a key AMPK effector regulating GLUT4 insertion into the plasma membrane and glucose uptake in muscle cells.
- This study provides new mechanistic insights into glucose homeostasis regulation in muscle.
- Tmod3 represents a potential therapeutic target for metabolic disorders.
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