Abstract
Using Astral DIA quantitative proteomics, this study characterized serum protein profiles and potential functions of goat milk from different altitude regions. A total of 1446 proteins were identified, with 1268, 1256, and 1346 proteins detected in high-altitude, mid-altitude, and low-altitude samples, respectively. The high-altitude sample contained 34 unique proteins and showed higher abundances of α-lactalbumin, serum albumin, and polymeric immunoglobulin receptor, whereas the low-altitude sample contained 87 unique proteins and higher abundances of several immune-related proteins, including osteopontin, lactoferrin, immunoglobulin, lysozyme, xanthine oxidase, lactoperoxidase, and GLYCAM1. Differentially expressed analysis identified 453, 452, and 113 differential proteins in high-altitude vs. low-altitude, mid-altitude vs. low-altitude, and high-altitude vs. mid-altitude comparisons, respectively. KEGG analysis showed that carbohydrate metabolism was enriched in comparisons involving the low-altitude sample, whereas amino acid metabolism was enriched between high-altitude and mid-altitude samples. Notably, HIF-1 signaling pathway was enriched in the high-altitude sample, suggesting hypoxia-associated proteomic adaptation.