乙烯利处理对棉花子叶DNA表观遗传变化的甲基化敏感扩增多态性(MSAP)分析  

Methylation Sensitive Amplified Polymorphism(MSAP) Analysis of DNA Epigenetic Changes of Cotton(Gossypium hirsutum L.)Cotyledons under Ethephon Treatment

作　　者：郭宁[1] 席晓广 张晓旭[1] 樊洪泓[1] 蔡永萍[1] 林毅[1] 孙旭[1] 

机构地区：[1]安徽农业大学生命科学学院,合肥230036

出　　处：《农业生物技术学报》2014年第9期1131-1140,共10页Journal of Agricultural Biotechnology

基　　金：安徽省教育厅自然科学基金(No.KJ2012A117);安徽省棉花产业技术体系(皖农科[2010]300号);安徽省棉花11.5创新团队(皖人才办[2011]2号)

摘　　要：棉花(Gossypium hirsutum L.)叶片早衰影响棉花产量和棉纤维质量,而乙烯利是一种重要的植物生长调节剂,对促进植物组织衰老有重要作用。DNA甲基化是表观遗传调控的重要组成部分,在高等植物的基因表达调控中发挥了重要作用。本研究应用甲基化敏感扩增多态性(methylation sensitive amplified polymorphism,MSAP)技术,探讨在不同乙烯利水平处理下,棉花子叶DNA甲基化水平和甲基化变化模式。结果显示,经300、500和700 mg/L乙烯利处理后,棉花子叶DNA甲基化比值分别为32.99%、35.45%和37.49%,都低于对照组(37.92%);和对照组相比,经不同浓度乙烯利处理后,棉花子叶DNA发生甲基化变化位点的比率分别是2.71%、3.63%和4.88%,而去甲基化位点的比率分别为10.66%、9.84%和9.23%,并且随着乙烯利浓度的增加,棉花子叶DNA甲基化位点与去甲基化位点之比逐渐提高;本研究鉴定了17个MSAP差异基因片段,这些片段与NCBI中已知的功能基因存在同源性,包括果胶甲酯酶基因、细胞色素P450、乙醇脱氢酶基因、肌动蛋白解聚因子、翻译延伸因子等和乙烯利诱导棉花子叶衰老相关基因。研究结果提示,在乙烯诱导棉花子叶衰老的进程中,DNA甲基化参与了棉花子叶衰老的调控,为从基因组水平上揭示乙烯诱导棉花衰老的调控机制提供理论依据。Leaf senescence affects the yields and fiber quality of cotton （Gossypium hirsutum L.）, while ethephon is an important plant growth regulator, which plays important role in promoting the senescence of plant tissues. DNA methylation is an important component of the epigenetic regulation, and plays a very important role in the regulation of gene expression in higher plants. The methylation sensitive amplified polymorphism （MSAP） technique was used to assess epigenetic variations of cotton cotyledons under ethephon treatment, which would help to isolate and identify methylation regulating genes during cotton cotyledons senescence. The results showed that the cotton cotyledons genomic DNA methylation ratios were 32.99%, 35.45% and 37.49%, respectively, lower than that of the control group （37.92%）, when they were treated with 300, 500 and 700 mg/L ethephon. In contrast with the control group, treated with 300, 500 and 700 mg/L ethephon, methylation and demethylation loci ratio of cotton cotyledons genomic DNA were 2.71%, 3.63%, 4.88% and 10.66%, 9.84%, 9.23%, respectively. The ratios of DNA methylation and demethylation increased gradually accompanied with the enhancement of ethephon treatment. Seventeen MSAP different fragments were identified, and NCBI Blast results showed that these different fragments were homologous to functional genes, including senescence-associated genes （such as pectin methylesterase gene）, abiotic stress-related genes （such as cytochrome P450）, signal transduction-related genes（such as alcohol dehydrogenase gene, cytoskeleton-related genes and actin depolymerizing factor）, and protein synthesis- related genes（such as translation elongation factor 1A-1）, which were associated with senescence of cotton cotyledons under ethephon treatment. In conclusion, in the ethylene-induced senescence course of cotton cotyledons, DNA methylation played an important role in the regulation of cotton cotyledons senescence, which provides a theoretical basis for regulation mechanism

关 键 词：棉花子叶 乙烯利 甲基化敏感扩增多态性(MSAP) DNA甲基化 

分 类 号：S562[农业科学—作物学]