稻曲病菌休眠与非休眠厚垣孢子的MSAP分析

本研究以稻曲病菌Ustilaginoidea virens黄色(非休眠)厚垣孢子、黑色(休眠)厚垣孢子、厚垣孢子萌发后产生的分生孢子(非休眠)3种孢子为材料,采用DNA甲基化敏感扩增多态性技术对供试材料基因组DNA进行甲基化分析,探究稻曲病菌休眠与非休眠厚垣孢子DNA甲基化的水平和模式。结果显示,3种形态孢子的基因组DNA甲基化水平差异明显,分生孢子基因组DNA中CCGG序列的总甲基化率为20.56%,黑色休眠厚垣孢子为25.63%,黄色非休眠厚垣孢子为33.52%。黄色和黑色的厚垣孢子主要是全甲基化模式,其全甲基化率高于半甲基化率,其中黄色厚垣孢子全甲基化率高达17.68%;分生孢子则是以半甲基化模式为主。结果对揭示稻曲病菌厚垣孢子休眠的分子机制,探究真核生物孢子的分子休眠机制有普遍意义。

DNA methylation sensitive amplification polymorphism analysis of dormant and non-dormant chlamydospores in Ustilaginoidea virens

Methylation sensitive amplification polymorphism (MSAP) analysis was performed to profile the DNA methylation levels and pattern of three forms of dormant and non-dormant chlamydospores and conidia in Ustilaginoidea virens. The results showed that the difference of DNA methylation was obvious among them. The total methylation rate of CCGG sequence in genomic DNA of conidia was 20.56%; the black chlamydospores (dormant) was 25.63%, and the yellow chlamydospores (non-dormant) was 33.52%. The fully-methylated ratio of yellow chlamydospores was up to 17.68%, the highest among the two kinds of chlamydospores and conidia. The main pattern was full-methylation in dormant and non-dormant chlamydospores of U. virens, while conidia DNA was dominated by hemi-methylation pattern. Therefore, this study would be helpful for the understanding the molecular mechanism of dormancy in chlamydospores of U. virens. It has a universal and theoretical value for the study of the molecular mechanism of dormancy in eucaryotes.