江苏农业学报2025，Vol.41Issue(3)：432-444,13.DOI:10.3969/j.issn.1000-4440.2025.03.002
紫色甘薯突变体形成的表观调控机制
Epigenetic regulatory mechanisms of purple sweetpotato mutant formation
摘要
Abstract
Purple sweetpotatoes are highly valued by consumers due to their rich content of anthocyanins.However,their frequent mutations seriously affect the stability of purple sweetpotato varieties.In this study,Ningzishu 4 and its mutant were used as research objects.The analysis of their phenotypes and physicochemical properties revealed that the mutant had significant changes in anthocyanin,β-carotene,and starch content,while there were no significant changes in yield and most phenotypes.Through transcriptome sequencing analysis,a total of 313 differentially expressed genes were identified.The rela-tive expression levels of genes(IbCHS,IbCHI,IbDFR,IbANS,and IbC4H)involved in anthocyanin synthesis and transcription factor-encoding genes(IbMYB R2R3,Ib-bHLH2,and IbWD40)in the mutant were significantly low-er than those in Ningzishu 4.In contrast,the relative ex-pression level of the gene(IbAGPL2)involved in starch synthesis in the mutant was significantly higher than that in Ningzishu 4.The relative expression levels of the gene IbC-MT2,predicted to be a DNA methyltransferase,and the gene IbJMJ25,predicted to be a histone demethylase,in the mutant were both upregulated compared with Ningzishu 4.By analyzing the changes in global methylation levels using N6-methyladenine dot blot(6mA),it was found that the DNA methy-lation level in the mutant was significantly higher than that in Ningzishu 4.Further analysis using bisulfite sequencing(BSP)revealed that the DNA methylation level of the transcription factor MYB2 in the mutant was increased.The results of Western blot showed that the modification levels of H3K9me2 and H3K27me2 in the mutant were significantly lower.The above results indicate that the phenotype of purple sweetpotato is due to changes in epigenetic modifications that inhibit anthocyanin synthe-sis,thereby causing the corresponding mutations.This study is the first to elucidate the mechanism of sweetpotato mutation from the perspective of epigenetic regulation.It not only provides new ideas for the epigenetic research of sweetpotato but also holds promise for developing new methods of directed breeding in sweetpotato based on epigenetic regulation.关键词
紫色甘薯/突变体/花青素/表观遗传/DNA甲基化/组蛋白修饰Key words
purple sweetpotato/mutant/anthocyanins/epigenetics/DNA methylation/histone modification分类
农业科技引用本文复制引用
刘帅,马佩勇,郭可,贾赵东,禹阳,张铅,边小峰..紫色甘薯突变体形成的表观调控机制[J].江苏农业学报,2025,41(3):432-444,13.基金项目
国家重点研发计划项目(2023YFE0111700) （2023YFE0111700）
国家自然科学基金项目(32101787) （32101787）
江苏省种业振兴揭榜挂帅项目[JBGS(2021)010] （2021）
国家甘薯产业技术体系项目(CARS-10) （CARS-10）
