Study On Differential Proteomics In Sex Differentiation Of Monoecious Pistacia Chinensis Bunge

The Pistacia chinensis Bunge is traditionally dioecious,and is one of the major trees to supply biomass energy in North China.However,the distribution of few male strains led to the continuous low yield of the cultivated P.chinensis Bunge species,thus dioecious has become an important factor restricting the improvement of the P.chinensis Bunge yield.The discovery of monoecious P.chinensis Bunge in recent years in North China has provided good raw materials to study the sex differentiation process of the P.chinensis Bunge.The objective of this study was to identify the differently expressed proteins in flower buds in two key sex differentiation phases in the monoecious P.chinensis Bunge,and to provide some clues to depict the sex determination process of the P.chinensis Bunge.In this study,the key phenophases of the flower bud differentiation were determined firstly in the monoecious P.chinensis Bung.Total protein was extracted from the flower bud samples,and then checked for quality and quantity.Then the label-free quantification technique was used for proteomic analysis through LC-MS/MS analysis on the peptide segements obtained using protease.The differentially expressed proteins wre detected.Bioinformatics analysis,including GO analysis and signal pathway analysis,was performed on the identified proteins,so as to determine the differentially expressed proteins and its associated metabolic pathways in male and bisexual flower buds in two key phenophases of the P.chinensis Bunge,(1)A total of 3,750 proteins were successfully identified in both bisexual and female flower buds in two key phenophases,and 104 of them were annotated in the databases of Sapindales.(2)The proteins related to oxidative stress resistance,ribosome activity,and photosynthetic function upregulated during the male primordium differentiation of P.chinensis Bunge in late May,indicating the increased anti-inverse capacity,ribosome activity and photosynthesis.On the other hand,proteins related to oxidative stress resistance up-regulated and proteins involved in photosynthesis down-regulated during the female primordium differentiation of the P.chinensis Bunge in early March next year,indicating the increased anti-inverse capacity and the weakened photosynthesis.(3)Compared to the differentially expressed proteins(DEPs)in flower buds in early March next year,some DEPs related to anti-inverse capacity only expressed in flower buds in late May,but the DEPs involved in the photosynthesis pathway all up-regulated,and the DEPs involved in the ribosome pathway all down-regulated,indicating the increased anti-inverse capacity and photosynthesis and the weakened ribosome activity at this time.(4)The Heat Shock Protein 90(Hsp90)was not expressed in either female or bisexual flower buds in Phenophase Ⅱ(early March next year),while down-regulated in bisexual flower buds in Phenophase I(late May).