ITRAQ-based Comparative Proteomic Analysis Of Oocytes In Vitro Maturation For Yak

Modern biological reproduction technology including embryo transplantation,external fertilization,and somatic cell nuclear transfer can promote rapid propagation of fine yak resources.For modern reproduction technologies,oocytes maturation in vitro is the pivotal step,the quality of mature oocytes is associated with the successful fertilization of oocytes and subsequent cleavage.Therefore,identifying and studying the proteomics of yak oocytes in different stages would help us understand early embryonic development process.In this study,we chosen GV oocytes and M? oocytes of yaks as research material,the cell protein was extracted.iTRAQ and LC-ESI-MSMS technology was used to determine the expression level of cellular protein and screen those differentially expressed protein between GV and MII oocytes.At last,we tried to investigate their roles during oocyte maturation.The results were below:1.Mascot 2.3.02 software was used to analyze the related information of mass spectrum gained by TripleTOF 5600 LC-MSMS system.A total of 1188 kinds of protein were identified,among of which 1067 kinds could be used for further quantitative analysis,which were mainly involved post-translational modification of proteins,conversion,chaperone,etc.2.Based protein abundance levels,we regarded those protein with variance ration > 1.2 and p value < 0.05 as differentially expressed protein.Compared with GV oocytes,there were 161 kinds of protein with differential expression,among of which 81 kinds of protein have an up-regulated expression level and 80 kinds of prtein have a down-regulated expression level.3.GO enrichment analysis showed that those proteins with different expression were mainly enriched in biological process,cellular competent,and molecular function.KEGG pathway enrichment analysis showed there were 145 kinds of differentially expressed protein were explainted and mainly involved in 162 pathways,including cellular metabolism related pathway,regulation of cell immune related pathway,Wnt signaling pathway,MAPK signaling pathway,etc.These enriched pathways may correlate with the oocyte maturation.4.Integrative analysis of proteome and transcriptome revealed a total of 1133 kinds of proteins were associated with the transcriptome,among which 63 kinds of differentially expressed were included.Moreover,there were 7 kinds of genes whose expression level in protein were consistent with gene transcription level.However,it is noteworthy no linear relationship was observed between the protein abundance and the corresponding gene transcriptional level.In summary,we analyze the oocytes proteome of yaks and dug some protein with differentially expression level,which made foundation for investigating molecular mechanism of oocyte maturation.