Identification And Characterization Of WD40 Gene Family In Peach

Prunus persica(L.)Batsch is an important stone fruit tree belonging to the family Rosaceae.It is native to China and has abundant germplasm resources.According to the color of the flesh,it is mainly divided into white-flesh peach,yellow-flesh peach,blood-flesh peach and green-flesh peach.The WD40 family of transcription factors is a family found in all eukaryotes that play an important role in regulating growth and development.The WD40 gene family have been identified and characterized in several plant species to date.There is very little information about the WD40 gene family in peach.In this study,we identified 220 WD40 family members in the peach genome,and these members were compared with phylogenetic analysis in Arabidopsis.In this study,this experiment mainly used ’TJSM’ blood-flesh peach as the main research object,white-flesh peach(ZX)as a control,using hidden Markov model to identify all WD40 superfamily members in peach;Phylogenetic and collinearity analysis using Arabidopsis thaliana and peach WD40 protein;in addition,qRT-PCR was used to analyze the expression levels of 54 WD40 genes in blood and white flesh peach at 5 developmental stages;The subcellular localization of 7 of these 54 WD40 proteins was analyzed by transient expression in N.benthamiana leaves.The main results are as follows:(1)220 WD40 family members were identified in the peach genome,and the 220 peach WD40 family genes and 237 Arabidopsis WD40 family genes were phylogenetically analyzed,and 220 peach WD40 family genes were further divided into five.Members of the WD40 family in each subfamily have a conserved Motif and gene structure.The 220 peach WD40 genes were distributed unevenly on chromosomes 1 to 8 of the peach genome.(2)58 pairs of paralogous WD40 gene members were found on 8 chromosomes of peach,and matched to 242 pairs of orthologous WD40 genes in peach and Arabidopsis.54 genes that may be associated with blood-flesh peach fruit traits were screened out among 220 peach WD40 family members,and the 54 WD40 genes of peaches have diverse expression patterns in blood and white flesh peach at five developmental stages.7 genes with differential expression were screened out among 54 genes that may be associated with blood-flesh peach fruit traits.Prupe.1G170200.1 gene may be involved in the regulation of anthocyanin synthesis in the peel and pulp of blood-peach peach fruit.(3)Through transient expression in the leaves of N.benthamiana,subcellular localization analysis revealed:The Prupe.6G211800.1 gene is only expressed on the cell membrane.Compared with the homologous gene AT3G49660.1 in Arabidopsis thaliana,it is presumed to be a membrane protein,the synthesis of anthocyanins involves the action of membrane proteins,it can be inferred that the function of Prupe.6G211800.1 may be related to the color of the blood-flesh peach and the stage of fruit development;The Prupe.1G428200.1 gene and the Prupe.1003200.1 gene are mainly expressed on the cell membrane and nucleus.Prupe.1G428200.1 gene compared with its homologous gene AT5G67320.1 in Arabidopsis(HOS15/OL11)analysis,Prupe.1G428200.1 gene may be related to leaf size and chilling stress response,based on the results of the expression,it may also be related to the color of the flesh of the blood-flesh peach;The Arabidopsis homologs of the Prupe.1003200.1 gene are AT1G62020.1 and AT2G21390.1.Based on conservation,it is inferred that it has a potential effect on the activity of transporters and structural molecules,in view of the synthesis process of plant anthocyanins,it is speculated that it may be involved in the regulation of the synthesis of anthocyanins in blood-flesh peach;The Prupe.1G558700.1 gene is densely located around the nuclear margin,but is relatively weakly located in the nucleoplasm,which is homologous to the AT1G80670.1 gene in Arabidopsis,presumably acting in mRNA export,spindle assembly,and chromosome segregation,regulating protein synthesis and indirectly regulating anthocyanin synthesis;The Prupe.5G116300.1 gene is located in the nucleus and cell membrane,and has strong signal,but the signal in the cytoplasm is weak.It is homologous to AT1G64350.1 in Arabidopsis thaliana,and it is presumed to play a role in plant-microbial symbiosis of peach;The Prupe.8G212400.1 gene and the Prupe.1G053600.1 gene are mainly located in the nuclear membrane and cell membrane,but are relatively weak in the nucleoplasm.Its homologous gene in Arabidopsis is AT5G43930.1,so it is speculated that the Prupe.8G212400.1 gene and the Prupe.1G053600.1 gene play a role in nucleic acid binding,according to the expression results,it was concluded that the Prupe.8G212400.1 gene may negatively regulate other genes to regulate the synthesis and accumulation of anthocyanins in the fruit to promote the color change of the flesh.This study laid the foundation for further functional verification of the WD40 gene in peach.(4)Seven peach WD40 genes(Prupe.6G211800.1,Prup.1G428200.1,Prupe.I003200.1,Prupe.5G116300.1,Prupe.1G053600.1,Prupe.1G558700.1,Prup.8G212400.1)were heterologously transformed into Arabidopsis thaliana.,all of the seven genes have obtained Ti transgenic seeds,and one(Prupe.6G211800.1)gene has obtained T2 generation transgenic seeds.