Proteome analysis using iTRAQ reveals the differentiation between Tibetan and ordinary ovalbumin peptides.

Ovalbumin peptides are food protein-derived fragments comprised of amino acid residues. The bioactive properties of the peptides are determined by the inherent amino acid composition and sequence of the peptide. The objective of this study was to evaluate the proteomics characteristics in Tibetan chicken egg ovalbumin peptides, compared to ordinary eggs, using isobaric tags for the relative and absolute quantification labelling technique (iTRAQ). The results showed that 165 proteins were identified and 56 proteins were significantly changed including 34 significantly upregulated and 22 significantly downregulated proteins. The more abundant proteins of the Tibetan ovalbumin peptides included vitellogenin-2, vitellogenin-1, vitellogenin, apolipoprotein A-I, and serum albumin, which were upregulated. A Gene Ontology (GO) analysis showed that these proteins mostly participated in biological processes and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that they may be associated with the peroxisome proliferator-activated receptor (PPAR) pathway, which is related to lipid metabolism. The Protein-Protein Interaction (PPI) analysis showed that these proteins significantly interacted. • The Tibetan egg ovalbumin peptide identification by proteome analysis was not reported before. • The difference of ovalbumin peptides of Tibetan egg and the ordinory in protein expression patterns and the difference of biochemical function on proteomic level are reported in this paper. • This study will help demonstrate molecular-level protein differences in ovalbumin peptides and may help reveal ovalbumin special effect on protein function of Tibetan egg. [ABSTRACT FROM AUTHOR]