Dataset Information

Phosphoproteomics of the Milk Fat Globule Membrane: new insights into lipid droplet secretion from the mammary epithelial cell

ABSTRACT: Lipid droplets are secreted into milk by a complex process which begins by burgeoning oflipids at the endoplasmic reticulum of the mammary epithelial cell (MEC). Lipid dropletsenveloped by organelle-derived phospholipids reach the apical pole of the cell where they arewrapped by the plasma membrane to be secreted as fat globules into milk. Analyzing the fineprotein composition of the Milk Fat Globule Membrane (MFGM), the triple-layeredmembrane surrounding milk lipid droplets can therefore provide mechanistic clues to betterunderstand lipid droplet biosynthesis and secretion pathways. We combined a high sensitiveQ Exactive LC-MS/MS analysis of MFGM-derived peptides with the use of an in-house database intended to improve protein identification in the goat species. Using this approach, we performed the identification of 442 functional groups of proteins in the MFGM from goatmilk. To get a more comprehensive view of intracellular mechanisms driving lipid dropletdynamics in the MEC, we decided to investigate for the first time whether MFGM proteinswere phosphorylated. A phosphopeptide enrichment approach let us pinpoint 271 sites ofphosphorylation on 124 unique goat MFGM proteins. Enriched gene ontology termsassociated with phosphorylated MFGM proteins were protein transport and actin cytoskeletonorganization. Gained data are discussed with regard to lipid secretory mechanisms in the MEC.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Capra Hircus (goat)

TISSUE(S): Epithelial Cell

SUBMITTER: HENRY CELINE

LAB HEAD: Christelle CEBO

PROVIDER: PXD001039 | Pride | 2015-05-12

REPOSITORIES: Pride

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Phosphoproteomics of the goat milk fat globule membrane: New insights into lipid droplet secretion from the mammary epithelial cell.

Henry Céline C Saadaoui Besma B Bouvier Frédéric F Cebo Christelle C

Proteomics 20150526 13

Mechanisms of milk lipid secretion are highly controversial. Analyzing the fine protein composition of the "milk fat globule membrane" (MFGM), the triple-layered membrane surrounding milk lipid droplets (LDs) can provide mechanistic clues to better understand LD biosynthesis and secretion pathways in mammary epithelial cells (MECs). We therefore combined a high-sensitive Q-Exactive LC-MS/MS analysis of MFGM-derived peptides to the use of an in-house database intended to improve protein identific ...[more]

PMID: 25737190

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Dataset Information

Phosphoproteomics of the Milk Fat Globule Membrane: new insights into lipid droplet secretion from the mammary epithelial cell

Publications

Phosphoproteomics of the goat milk fat globule membrane: New insights into lipid droplet secretion from the mammary epithelial cell.

Similar Datasets

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