Multi-omics integration identifies lipid transport proteins and specific triglycerides as compositional signatures of buffalo milk fat globule membrane

Buffalo milk fat globule membrane (MFGM) exhibits specific molecular-level remodeling of triglyceride (TG) species, yet its comprehensive protein-lipid association network remains incompletely characterized. Here, we performed parallel lipidomics and label-free quantitative proteomics on MFGM from buffalo (n=3), Holstein (n=3), and Jersey (n=3) cows. Lipidomics identified 1,550 lipid species; although no significant differences in overall TG abundance were observed across chain-length categories, TGs represented the most abundant differential lipid class, with 71 upregulated species. Proteomics revealed 232 upregulated and 231 downregulated proteins. STRING analysis identified a nine-protein lipid transport sub-network (APOA1, APOA2, VLDLR, LIPG, SAA2, HP, M-SAA3.2, HBA, HBB). Multi-omics integration via stringent Spearman correlation (|r| > 0.85, P < 0.05) refined this module to five core proteins (HBA, HBB, HP, APOA1, LIPG) exhibiting distinct topological relationships with the upregulated TGs. This study provides a systematic compositional dataset of buffalo MFGM, establishes a reproducible small-sample multi-omics workflow, and proposes potential molecular markers based on co-abundance patterns of lipid transport proteins and specific saturated TGs for buffalo milk authenticity authentication.