Study on Proteomics of Colostrum and Mature Milk of Guanzhong Dairy Goat Based on TMT Technology

Goat milk is an integral part of china' s milk industry, in order to explore the protein group differences of guanzhong dairy goats in different lactation periods. In this study, TMT technology was used to analyze the differences between the colostrum group and mature milk histone group of Guanzhong dairy goats. The credible proteins were analyzed and identified by PCA and univariate analysis. Combined with the screening conditions of differential proteins: Fold change > 1.2 and P-value<0.05, the differential proteins were obtained. Enrichment analysis of differential proteins was performed using GO and KEGG databases. The results showed that a total of 241 differential proteins were screened out in colostrum and mature milk, of which 80 proteins were significantly up-regulated and 161 proteins were significantly down-regulated. Differentially expressed proteins are mainly enriched in Acute-phase response, Lactose biosynthetic process, Ro Protein Signal Transfer, Extracellular region, Extracellular space, Golgi apparatus, GTPase activity and GTP binding. The KEGG pathway enrichment analysis showed that the most significantly different proteins were enriched in the Ras signaling pathway, chemokine signaling pathway, complement pathway, Rap1 signaling pathway, and PPAR signaling pathway. Our results showed that goat colostrum showed more metabolic pathways related to immune diseases and mature milk showed more pathways related to cancer, which promoted the study of protein polymorphism in goat milk and It provides a theoretical basis for further study on the nutritional value of goat milk in different lactation periods.