小麦杀配子染色体单体附加系CS-2C的DNA甲基化变异分析

Variation Analysis of DNA Methylation of Gametocidal Chromosome 2C

本研究利用MSAP方法检测普通小麦中国春(CS)、中国春-杀配子染色体2C单体附加系(CS-2C单体附加系)的DNA甲基化变异,探究DNA甲基化与杀配子染色体的关系。结果表明,CS-2C单体附加系5'-CCGG位点的胞嘧啶甲基化水平(45.33%)高于CS(40.35%),其中全甲基化率与半甲基化率均有所升高。与CS相比,CS-2C单体附加系的5'-CCGG位点发生了明显的胞嘧啶甲基化模式变异,以胞嘧啶甲基化升高为主,其中CG位点甲基化变异幅度高于CHG位点甲基化变异幅度。通过对甲基化差异片段进行测序鉴定,结果显示部分差异片段与普通小麦Sukkula-like转座子等具有高度同源性。由此推测,转座子可能在杀配子作用机制中起作用。本研究为揭示杀配子染色体的分子机制奠定了基础。

In this investigation,the levels and patterns of DNA methylation of common wheat Chinese Spring（ CS） and CS- 2C gametocidal chromosome monosomic addition line（ CS- 2C） were identified using MSAP method,to explore the relationship between the DNA methylation and the gametocidal chromosome. The results show that,cytosine methylation level of CS- 2C monosomic addition line 5 ＇- CCGG sites（ 45. 33%） was higher than that of CS（ 40. 35%）,the full methylated rate and hemi-methylated rate were increased. Obvious variation of cytosine methylation at 5＇- CCGG sites was detected,in which CG methylation variation range was higher than that of CHG methylation variation. After collecting and sequencing the differentially methylated DNA fragments some of fragments homologous with Carazinho transposon Sukkula-like etc were found. It can be proposed that transposons may play a role in gametocidal mechanism. The purpose of this study was to reveal the molecular mechanism of gamtocidal chromosome.