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Differential gene expression in skeletal muscle cells after membrane depolarization
Nevenka Juretić1, Ulises Urzúa, David J Munroe
1Centro de Estudios Moleculares de la Célula, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile.
Journal of Cellular Physiology
|December 6, 2006
Summary
High potassium stimulation alters gene expression in skeletal muscle cells, impacting metabolism and cell communication. This depolarization-induced gene expression may explain the calcium-dependent plasticity of muscle tissue.
Area of Science:
- Molecular Biology
- Cell Biology
- Physiology
Background:
- Skeletal muscle exhibits significant plasticity in response to contractile activity.
- Adaptive responses like hypertrophy involve changes in gene transcription.
- Understanding gene regulation by stimuli is crucial for muscle adaptation.
Purpose of the Study:
- To identify genes regulated by a depolarizing stimulus in skeletal muscle cells.
- To investigate the role of calcium signaling in depolarization-induced gene expression.
- To elucidate the molecular mechanisms underlying skeletal muscle plasticity.
Main Methods:
- Utilized 22K mouse oligonucleotide microarrays to analyze gene expression.
- Isolated total RNA from C2C12 myotubes at various time points post-high K+ stimulation.
- Employed Loess normalization and statistical analysis to identify differentially expressed genes.
Main Results:
- Identified 423 differentially expressed genes (P < 0.01) in response to K+-depolarization.
- Depolarization primarily affected genes related to metabolism, cell communication, and stress response.
- Observed induction of Ca2+ signaling pathway genes at 4 hours and increased Tnni1 and Acta1 mRNA levels.
Conclusions:
- K+-depolarization regulates a specific set of genes in skeletal muscle cells.
- Calcium signaling plays a role in the early steps of depolarization-induced gene expression.
- Depolarization-induced gene expression contributes to the calcium-dependent plasticity of skeletal muscle.
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