Abstract: The purpose of this study was to analyze the differential expression proteins(DEPs) of yak pulmonary arterial smooth muscle cells (PASMCs) under different culture conditions of hypoxia and normoxia by using TMT technology, so as to understand DEPs for PASMCs of plateau yak. In this study, PASMCs were cultured by sticking culture method and cultured for 72 h under hypoxia and normoxia conditions, respectively. Then cells were collected and the total protein of cells was extracted. DEPs were screened for analysis using TMT labeled protein quantitative technology, and GO functional annotation and KEGG pathway analysis were performed. A total of 6 859 proteins were obtained by comparing the samples in 2 groups of PASMCs under hypoxia and normoxia. With the standard of FC(fold change) ≥ 1.3 or ≤ 0.78 and P<0.05, a total of 531 DEPs were obtained, among them, 186 DEPs were up-regulated and 345 DEPs were down-regulated. The results of enrichment analysis showed DEPs were mainly enriched in the hypoxia adaptation related pathways such as central carbon metabolism, glycolysis and glucose metabolism synthesis, HIF-1 signaling pathway, and biosynthesis of secondary metabolites. Seven important DEPs (PGK, HK, LDH, PGAM, pfkA, IL6ST and PDK1) were found in these pathways. Subcellular localization of plasma membrane (28.9%) accounted for the highest proportion. Epidermal growth factor-like domain was the main domain in domain analysis. The results indicated that DEPs were enriched in metabolism, enzyme activity, hypoxia adaptation and other related categories and pathways. Seven important DEPs (PGK, HK, LDH, PGAM, pfkA, IL6ST and PDK1) may be related to the adaptation to hypoxia environment. These results provide the theoretical support for further study on adaptation of yak PASMCs to hypoxia.

Key words: yak, PASMCs, hypoxia and normoxia, TMT technology