Systems biology of skeletal muscle: Fiber type as an organizing principle

Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN, USA.
Wiley Interdisciplinary Reviews Systems Biology and Medicine (Impact Factor: 3.21). 09/2012; 4(5):457-73. DOI: 10.1002/wsbm.1184
Source: PubMed


Skeletal muscle force generation and contraction are fundamental to countless aspects of human life. The complexity of skeletal muscle physiology is simplified by fiber type classification where differences are observed from neuromuscular transmission to release of intracellular Ca2+ from the sarcoplasmic reticulum and the resulting recruitment and cycling of cross-bridges. This review uses fiber type classification as an organizing and simplifying principle to explore the complex interactions between the major proteins involved in muscle force generation and contraction. WIREs Syst Biol Med 2012. doi: 10.1002/wsbm.1184
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    • "While further details of upstream regulation are unclear, the expression of MyHC isoforms with different molecular properties, for example variable cross-bridge lengths with actin during contraction, underlies part of the functional differences between fiber types (reviewed in [11,24]). Additionally, specific MyHC isoforms are combined with fiber type-specific isoforms of the Troponin–Tropomyosin complex to adjust the calcium sensitivity of different fiber types. "
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