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High-throughput Screening for Protein-based Inheritance in S. cerevisiae
Published on: August 8, 2017
Prion protein expression and functional importance in skeletal muscle
Jeffrey D Smith1, Jennifer S Moylan, Brian J Hardin
1Department of Physiology, University of Kentucky, Lexington, 40536, USA.
Antioxidants & Redox Signaling
|April 2, 2011
Summary
Prion protein (PrP) deficiency in skeletal muscle increases oxidant activity and impairs muscle function and size in adult animals. This highlights PrP
Area of Science:
- Muscle physiology
- Neuroscience
- Biochemistry
Background:
- Skeletal muscle expresses prion protein (PrP), which influences neuronal oxidant activity.
- The specific role of PrP in skeletal muscle function and redox homeostasis is not well understood.
Purpose of the Study:
- To investigate the hypothesis that PrP deficiency increases oxidant activity in skeletal muscle.
- To determine the effects of PrP deficiency on redox-sensitive functions, including muscle contraction and glucose uptake.
- To assess the impact of PrP deficiency on skeletal muscle size and contractile properties.
Main Methods:
- Real-time polymerase chain reaction and Western blot analysis were used to quantify PrP mRNA and protein levels in various mouse muscles, human diaphragm, and C2C12 myotubes.
- PrP-deficient mice and morpholino-knockdown myotubes were utilized to study the effects of PrP deficiency.
- Oxidant activity was measured using dichlorofluorescin oxidation, and specific muscle force was assessed in murine diaphragm fiber bundles.
Main Results:
- PrP expression levels and glycosylation patterns varied significantly among different mouse skeletal muscles and in human diaphragm.
- PrP deficiency led to decreased body weight and muscle mass (EDL).
- Cytosolic oxidant activity was elevated in PrP-deficient muscle fibers and myotubes, and specific muscle force was reduced in adult PrP-deficient mice.
Conclusions:
- Prion protein (PrP) content exhibits variability across different skeletal muscles.
- PrP is crucial for maintaining redox homeostasis, muscle size, and contractile function in adult animals.
- These findings establish a direct role for PrP in skeletal muscle physiology.
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