Genome-Wide DNA Methylation Of Seeds Located On Different Parts Of Maize Ear

DNA methylation is one of the major modifications to epigenetics.Many biological processes involved in cells play an important role in plant growth and development,genomic imprinting and responses to stress.In this study,maize methylated immunoprecipitation(MeDIP-seq)technique was used to study the methylation of whole genome DNA in the upper and middle seeds of maize hybrids Zhengdan 958 at 0h and 24 h.Some differential methylation genes were analyzed by McrBC-PCR.The MeDIP-seq data and RNA-seq data were combined to detect the expression level of some differential methylation genes.The mechanism of seed germination was studied from the perspective of DNA methylation.The main results are as follows:1.Analysis of Genomic DNA Methylation of Maize Ear at Different Absorption Time and Different Seeds by MeDIP-seq.The results indicate that the number of methylation differential genes in the 0h seed is much longer than that for 24 h.Compared with the upper seeds,the number of methylated up-regulated genes was found to be higher than that of the down-regulated genes,and the number of methylation down-regulated genes was higher than that of the up-regulated genes.2.MeDIP-seq analysis showed that the methylation of the promoter region was more than that of the gene region,and the methylation of the intron in the gene region was more than that of the exon.A total of 7264 differential methylation genes were detected in the seeds of 0h and the seeds were detected by 3047 differential methylation gene.These differential methylation genes encode proteins involved in chromatin and chromosome structure,DNA repair,energy metabolism,N metabolism,starch and sucrose metabolism,DNA damage repair and replication,translation initiation,signal transduction and other processes.3.The results showed that the methylation of the DNA promoter region was negatively correlated with the gene expression.The results showed that the methylation of the whole genome DNA and the RNA-seq data of different ear seeds were compared and analyzed.Subunit methylation decreased,gene expression increased.4.The methylation levels of 16 genes was verified by McrBC-PCR.It was found that the DNA methylation difference between 14 seeds(87.5%)was consistent with MeDIP-seq.