Genome-Wide Analysis And Expression Pattens Of SET Domain Gene In Brassica Oleracea

Brassica oleracea Linn.var.capitata DC,a biennial herbage of Cruciferae is a species of Brassica.It has been cultivated throughout the world and an important leaf vegetables.The epigenetic regulation mechanism remained conserved during the process of plant development,of them histonelysine methylation is one of the most important kind.The majority of the histone lysine methyltransferases(HKMTases)conferring such modications are proteins with a conserved SET domain responsible for the enzymatic activity which is wildly existed in eukaryotes.The function of SET domain genes in plants are very complex as they participate in protein methylation,chromosome structure adjustment,and gene expression regulation,and play important roles in plant development.Bioinformatics analysis of SET domain genes in Brassica oleracea,including the basic information about SET domain genes,phylogenetic relationships,domain distribution,intron–exon organization and physical locations.In the same time,we study the sequence characterization analysis and expression profile of SET domain genes in Brassica oleracea ‘Bo01-12B'.The main results are summarized as follow:1.The Brassica oleracea genomes encode 29 SET domain genes.These SET domain genes were found to bedistributed unevenly across 9 chromosomes in the Brassica oleracea genome,the chromosomes one hasnone especially.The length of the SET gene open reading frames(ORFs)varied from 405 bp for Bol044707 to 5,088 bp for Bol027564,with the respective coding potential of 134 and 1,695 amino acids.The intron–exon organization shows that the SET domain genesmay have zero intron and up to more than 20 introns.16 SETdomain proteins is alkaline.2.The 29 SET domain genes in Brassica oleracea were organized into seven major groups(Class I-VII)according to the unrooted phylogenetic tree and the distribution of other conserved domains.The motif of Class I is SANT-SET,Class II performed as AWS-SET-post-SET,the motif of Class III is PWWP-PHD-PHD-SET-post-SET,Class IV performed as PHD-SET,the motif of Class V is SRA-pre-SET-SET,Class VI performed as SET-post-SET,and Class VII contains only one SET domain.3.The qRT-PCR result in Brassica oleraceademonstrated that the seven SET domain genes(Bol040761,Bol030053,Bol042363,Bol043727,Bol025176,Bol027607,Bol011910)were expressed in the roots,stems,buds and flowers except the leaves.The SET domain genes showed very high expression levels in pollen,followed by the roots.The Semi-quantitative RT-PCR showed that SET domain genesexpressed in mostly sporogenous cell to pollen mother cell stage.