Single muscle fiber proteomics reveals unexpected mitochondrial specialization
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Updated: Apr 17, 2026

Measurement of Protein Import Capacity of Skeletal Muscle Mitochondria
Published on: January 7, 2022
Marta Murgia1, Nagarjuna Nagaraj2, Atul S Deshmukh3
1Department of Proteomics and Signal Transduction, Max-Planck-Institute of Biochemistry, Martinsried, Germany Department of Biomedical Sciences, University of Padova, Padua, Italy mmurgia@biochem.mpg.de stefano.schiaffino@unipd.it mmann@biochem.mpg.de.
Abstract:
Mammalian skeletal muscles are composed of multinucleated cells termed slow or fast fibers according to their contractile and metabolic properties. Here, we developed a high-sensitivity workflow to characterize the proteome of single fibers. Analysis of segments of the same fiber by traditional and unbiased proteomics methods yielded the same subtype assignment. We discovered novel subtype-specific features, most prominently mitochondrial specialization of fiber types in substrate utilization. The fiber type-resolved proteomes can be applied to a variety of physiological and pathological conditions and illustrate the utility of single cell type analysis for dissecting proteomic heterogeneity.
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