title: Identification of differentially expressed proteins in ruminal epithelium in response to a concentrate-supplemented diet.
abstract: Ruminal epithelium adapts to dietary change with well-coordinated alterations in metabolism, proliferation, and permeability. To further understand the molecular events controlling diet effects, the aim of this study was to evaluate protein expression patterns of ruminal epithelium in response to various feeding regimes. Sheep were fed with a concentrate-supplemented diet for up to 6 wk. The control group received hay only. Proteome analysis with differential in gel electrophoresis technology revealed that, after 2 days, 60 proteins were significantly modulated in ruminal epithelium in a comparison between hay-fed and concentrate-fed sheep (P < 0.05). Forty proteins were upregulated and 20 proteins were downregulated in response to concentrate diet. After 6 wk of this diet, only 14 proteins were differentially expressed. Among these, 11 proteins were upregulated and 3 downregulated. To identify proteins that were modulated by dietary change, two-dimensional electrophoresis was coupled with liquid chromatography electrospray ionization mass spectrometry. The differential expression of selected proteins, such as esterase D, annexin 5, peroxiredoxin 6, carbonic anhydrase I, and actin-related protein 3, was verified by immunoblotting and/or mRNA analysis. The identified proteins were mainly associated with functions related to cellular stress, metabolism, and differentiation. These results suggest new candidate proteins that may contribute to a better understanding of the signaling pathways and mechanisms that mediate rumen epithelial adaptation to high-concentrate diet.
authors.affiliation: Institute of Veterinary Biochemistry, Freie Universität Berlin, Germany. bondzio@zedat.fu-berlin.de
authors.forename: Angelika
authors.initials: A
authors.lastname: Bondzio
authors.forename: Christoph
authors.initials: C
authors.lastname: Gabler
authors.forename: Brit
authors.initials: B
authors.lastname: Badewien-Rentzsch
authors.forename: Petra
authors.initials: P
authors.lastname: Schulze
authors.forename: Holger
authors.initials: H
authors.lastname: Martens
authors.forename: Ralf
authors.initials: R
authors.lastname: Einspanier
mesh_terms: D025181:ATP Synthetase Complexes / Q000378:metabolism; D051378:Actin-Related Protein 3 / Q000378:metabolism; D000222:Adaptation, Physiological; D043383:Adenosylhomocysteinase / Q000378:metabolism; D000818:Animals; D017305:Annexin A1 / Q000378:metabolism; D017304:Annexin A5 / Q000378:metabolism; D015153:Blotting, Western; D024401:Carbonic Anhydrase I / Q000378:metabolism; D019587:Dietary Supplements; D015536:Down-Regulation; D004848:Epithelium / Q000378:metabolism* / Q000502:physiology; D005260:Female; D015870:Gene Expression; D007521:Isocitrate Dehydrogenase / Q000378:metabolism; D008297:Male; D008780:Methyltransferases / Q000378:metabolism; D054465:Peroxiredoxin VI / Q000378:metabolism; D019704:Protein Disulfide-Isomerases / Q000378:metabolism; D011506:Proteins / Q000378:metabolism*; D020543:Proteome / Q000378:metabolism; D006180:Proton-Translocating ATPases / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism*; D011897:Random Allocation; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012756:Sheep; D013279:Stomach, Ruminant / Q000378:metabolism* / Q000502:physiology; D013869:Thiolester Hydrolases / Q000378:metabolism; D057825:Two-Dimensional Difference Gel Electrophoresis; D015854:Up-Regulation
chemical_list: D051378:Actin-Related Protein 3; D017305:Annexin A1; D017304:Annexin A5; D011506:Proteins; D020543:Proteome; D012333:RNA, Messenger; D007521:Isocitrate Dehydrogenase; D054465:Peroxiredoxin VI; D008780:Methyltransferases; C022745:thiopurine methyltransferase; D025181:ATP Synthetase Complexes; D013869:Thiolester Hydrolases; C020149:s-formylglutathione hydrolase; D043383:Adenosylhomocysteinase; D006180:Proton-Translocating ATPases; D024401:Carbonic Anhydrase I; D019704:Protein Disulfide-Isomerases