Proteomic analysis of milk proteins from Gannan yak, cattle‑yak, and Holstein cattle

Using tandem mass tag (TMT) quantitative proteomics, we identified and quantified differentially expressed proteins (DEPs) among three types of milk samples: Gannan yak milk proteins (YMP), Gannan cattle‑yak milk proteins (CYMP), and Holstein milk proteins (HMP). A total of 648 proteins were quantitatively analyzed.
Compared with HMP, the DEPs in YMP and CYMP were predominantly enriched in immune‑related pathways, including the complement and coagulation cascades, the PPAR signaling pathway, and the phagosome. In contrast, the DEPs identified from the CYMP vs. YMP comparison were mainly associated with metabolic pathways, particularly the ribosome pathway.