Analysis Of The Transcriptome And Proteome Of Shoot Apical Meristem In Winter Wheat At Different Developmental Stages

Triticum aestivum L.is not only the main food crop in China,but also one of the most important food crops in the world.Flowering is the core process of wheat growth and development.Winter wheat must go through a long period of low temperature to initiate flower bud formation and floral organ development.This process is called vernalization.Vernalization of wheat is closely related to the quality and yield of wheat,therefore,vernalization of wheat has always been a hot issue for breeders.In order to better understand the molecular regulation mechanism of winter wheat vernalization,the shoot apical meristem of winter wheat cultivar Shimai 22 was collected at three-leaf stage(S1),winter dormancy stage(S2),spring green-up stage(S3),and jointing stage(S4)for transcriptome and proteome analysis.The main results are as follow:1.Transcriptome sequencing analysis: after high-throughput Illumina sequencing,103578 genes were identified in four periods.With fpkm ≥ 5,and Padj < 0.05 as the screening criteria,13779 differential expression genes(DEGs)were screened and 12 DEGs were screened for qRT-PCR verification.The results showed that the data of transcriptome sequencing were basically the same as that of qRT-PCR.These results not only verify the existing knowledge,but also show the reliability of this high-throughput sequencing and the complexity of vernalization mechanism.The clustering results of DEGs showed that the expression patterns of genes in three stages were similar,and there were significant differences between them.Several differentially expressed genes related to cold stress,defense and photosynthesis were screened out in winter(S2 vs S1)and recovery growth period(S3 vs S1).Several known vernalization genes,MADS box transcription factors,MYB transcription factors,DELLA proteins and other differentially expressed genes related to flowering were screened out in flower bud differentiation(S3 vs S2)and flower development(S4 vs S3).At the same time,a large number of mi RNA target genes were found to play an important role in the regulation of wheat development.2.Proteome sequencing analysis: after mass spectrometry analysis and identification,a total of 7370 proteins were identified in four stages,with FC > 1.5 or FC < 2 / 3,p-value < 0.05 as the screening criteria to screen the differentially abundant proteins(DAPs).The results of daps clustering showed that the expression patterns of genes were similar in three-leaf stage,winter dormancy stage and spring green-up stage,and the expression patterns were significantly different from those in jointing stage.Functional enrichment analysis and subcellular location analysis showed that daps enriched to plastid structure,chlorophyll metabolism,photosynthesis and other pathways in vegetative growth stage.At the stage of reproductive growth,a large number of cells are enriched to transport,endoplasmic reticulum processing,vesicle transport and so on.The calcium signaling pathway,temperature responsive protein and embryo development run through the whole process of Wheat Vernalization.3.Correlation analysis: the correlation of DEGs at mRNA level and the DAPs at protein level varied with deferent developmental stages.The correlation between DEGs and DAPs in the three-leaf stage,overwintering stage and greenup stage was low,while the correlation at the jointing stage was relatively high,reflecting the complexity of transcription,post transcriptional regulation,translation and post translational modification.