The experiment aimed to study the proteome variation in a yeast strain (YS031), which chromosome II was artificially synthezied, compared with the wild type strain (BY4741). Proteins were extracted from the yeast cells and digested with trypsin. The peptides were label with iTRAQ, separated with 2D LC (SCX and RP) and detected with a Q-Exactive MS. Proteome identification and quantification were performed with Mascot2.3 and iQuant3.0.