DAC对玉米DNA甲基化影响及基因表达量变化的研究

Effect of DAC on DNA Methylation and Its Gene Expression in Maize

以5-氮杂-2脱氧胞苷(DAC)处理相应对照玉米幼苗叶片为材料构建转录组测序文库,采用Illumina测序平台进行测序,对差异表达基因进行GO功能分类和KEGG通路分析。最终筛选到差异基因1072个,其中,上调表达基因为646个,下调表达基因为426个。将差异基因富集的生物过程和信号通路进行GO分析,发现主要集中于细胞部分、细胞过程、代谢途径及催化活性等条目中。KEGG分析发现,差异基因主要集中在过氧化物酶体、半乳糖代谢、苯丙烷生物合成及植物激素信号转导等代谢通路中。结果表明,代谢途径的细胞过程、代谢过程、催化活性、苯丙烷生物合成、过氧化物酶体、半乳糖代谢以及植物激素信号转导可能在玉米生长发育中起主导作用。通过亚硫酸盐测序对筛选的3个差异表达基因进行DNA甲基化水平分析,发现处理组CG、CHG位点甲基化率下降显著,由此表明DNA甲基化影响基因的表达。

DAC-treated corresponding control maize seedling leaves were used as materials to construct a transcriptome sequencing library.Illumina sequencing platform was used for sequencing.Differentially expressed genes were classified by GO function and KEGG pathway analysis.1072 differential genes were selected,of which 646 genes were up-regulated and 426 genes were down-regulated.The GO analysis of the collected biological processes and signal pathways found that it was mainly concentrated in the cell parts,cellular processes,metabolic pathways,and catalytic activities;and KEGG analysis found that the differential genes were mainly concentrated in peroxisomes,galactose metabolism,Phenylpropane biosynthesis and hormonal signal transduction in metabolic pathways.The results indicate that the cellular process,metabolic process,catalytic activity,phenylpropane biosynthesis,peroxisome,galactose metabolism,and plant hormone signal transduction of metabolic pathways may play a leading role in the growth and development of maize.Analysis of DNA methylation levels of the three differentially expressed genes screened by sulfite sequencing revealed that the methylation rates of CG and CHG sites in the treatment group decreased significantly,thus indicating that DNA methylation affected gene expression.