title: The sheep milk fat globule membrane proteome.
abstract: Milk fat globule membranes (MFGM) are three-layered structures that enclose fat droplets, and are composed by an internal monolayer of endoplasmic reticulum origin, surrounded by a bilayer derived from the apical membrane of the lactating cell. In this work, an optimized protein extraction method was applied to sheep MFGM, and extracts were subjected to SDS-PAGE separation followed by shotgun LC tandem mass spectrometry (GeLC-MS/MS) for identification and characterization. In total, 140 unique sheep MFGM proteins (MFGMPs) were identified. All protein identification data were subjected to Gene Ontology (GO) classification for localization and function. Moreover, the relative abundance of all identified MFGMPs was estimated by means of the normalized spectral abundance factor (NSAF) approach, and GO abundance classes were obtained. The data gathered in this work provide a detailed picture of the proteome expressed in healthy sheep MFGs, and lay the foundations for future studies on sheep lactation physiology and on its alterations in pathological conditions.
authors.affiliation: Porto Conte Ricerche Srl, Tramariglio, Alghero (SS), Italy.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Pisanu
authors.forename: Stefania
authors.initials: S
authors.lastname: Ghisaura
authors.forename: Daniela
authors.initials: D
authors.lastname: Pagnozzi
authors.forename: Grazia
authors.initials: G
authors.lastname: Biosa
authors.forename: Alessandro
authors.initials: A
authors.lastname: Tanca
authors.forename: Tonina
authors.initials: T
authors.lastname: Roggio
authors.forename: Sergio
authors.initials: S
authors.lastname: Uzzau
authors.forename: Maria Filippa
authors.initials: MF
authors.lastname: Addis
mesh_terms: D000818:Animals; D002417:Cattle; D002462:Cell Membrane / Q000378:metabolism*; D002850:Chromatography, Gel / Q000379:methods; D002853:Chromatography, Liquid / Q000379:methods; D004591:Electrophoresis, Polyacrylamide Gel; D004721:Endoplasmic Reticulum / Q000378:metabolism; D006017:Glycolipids / Q000378:metabolism*; D006023:Glycoproteins / Q000378:metabolism*; D066292:Lipid Droplets; D013058:Mass Spectrometry / Q000379:methods; D008565:Membrane Proteins / Q000737:chemistry*; D020543:Proteome; D040901:Proteomics / Q000379:methods*; D012756:Sheep
chemical_list: D006017:Glycolipids; D006023:Glycoproteins; D008565:Membrane Proteins; D020543:Proteome; C110367:milk fat globule