title: Differential expression of sarcoplasmic proteins in four heterogeneous ovine skeletal muscles.
abstract: Fiber-type distribution is known to vary widely within and between muscles according to differences in muscle functions. 2-DE and MALDI-MS were used to investigate the molecular basis of muscle fiber type-related variability. We compared four lamb skeletal muscles with heterogeneous fiber-type composition that are relatively rich in fast-twitch fiber types, i.e., the semimembranosus, vastus medialis, longissimus dorsi, and tensor fasciae latae (TL). Our results clearly showed that none of the glycolytic metabolism enzymes detected, including TL which was most strongly glycolytic, made intermuscular differentiation possible. Muscle differentiation was based on the differential expression of proteins involved in oxidative metabolism, including not only citric acid cycle enzymes but also other classes of proteins with functions related to oxidative metabolism, oxidative stress, and probably to higher protein turnover. Detected proteins were involved in transport (carbonate dehydratase, myoglobin, fatty acid-binding protein), repair of misfolding damage (heat shock protein (HSP) 60 kDa, HSP-27 kDa, alpha-crystallin beta subunit, DJ1, stress-induced phosphoprotein), detoxification or degradation of impaired proteins (GST-Pi, aldehyde dehydrogenase, peroxiredoxin, ubiquitin), and protein synthesis (tRNA-synthetase). The fractionating method led to the detection of proteins involved in different functions related to oxidative metabolism that have not previously been shown concomitancy.
authors.affiliation: Unité Qualité des Produits Animaux, INRA, St-Genès-Champanelle, France.
authors.forename: Muriel
authors.initials: M
authors.lastname: Hamelin
authors.forename: Thierry
authors.initials: T
authors.lastname: Sayd
authors.forename: Christophe
authors.initials: C
authors.lastname: Chambon
authors.forename: Jaques
authors.initials: J
authors.lastname: Bouix
authors.forename: Bernard
authors.initials: B
authors.lastname: Bibé
authors.forename: Dragan
authors.initials: D
authors.lastname: Milenkovic
authors.forename: Hubert
authors.initials: H
authors.lastname: Leveziel
authors.forename: Michel
authors.initials: M
authors.lastname: Georges
authors.forename: Alex
authors.initials: A
authors.lastname: Clop
authors.forename: Penka
authors.initials: P
authors.lastname: Marinova
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Laville
mesh_terms: D000818:Animals; D005260:Female; D020869:Gene Expression Profiling; D008297:Male; D009124:Muscle Proteins / Q000096:biosynthesis* / Q000235:genetics; D018482:Muscle, Skeletal / Q000378:metabolism*; D052097:Quadriceps Muscle / Q000378:metabolism; D012519:Sarcoplasmic Reticulum / Q000378:metabolism*; D012756:Sheep
chemical_list: D009124:Muscle Proteins