《植物生理学报》 2018, 54(10): 1596-1604

盐胁迫下蒺藜苜蓿MtMYBS1的DNA甲基化和组蛋白修饰状态分析

董蔚, 刘锡江, 高天雪, 宋玉光^*

曲阜师范大学生命科学学院, 山东曲阜273165

通信作者：宋玉光；E-mail: SYG-0423@163.com

摘　要：

表观遗传修饰尤其是DNA甲基化和组蛋白修饰在基因表达调控中起重要“开关”作用。前期研究证实蒺藜苜蓿(Medicago truncatula) MtMYBS1是参与植物盐胁迫应答的重要功能基因。本文采用反转录PCR (RTPCR)、重亚硫酸盐测序PCR (BSP)和染色质免疫沉淀(ChIP)等技术分析了MtMYBS1在盐胁迫过程中的表达、DNA甲基化及组蛋白修饰状态。盐胁迫下伴随着MtMYBS1的上调表达, 其启动子区及3′末端区的DNA甲基化修饰水平逐渐降低, 而启动子区及翻译起始位点附近组蛋白H3K9ac修饰水平逐渐升高。进一步相关性分析发现, 盐胁迫下MtMYBS1的表达与其DNA甲基化修饰水平呈负相关, 而与组蛋白H3K9ac的修饰呈正相关。该研究为深入了解MtMYBS1参与蒺藜苜蓿盐胁迫应答过程中的表达调控提供理论参考。

关键词：蒺藜苜蓿; DNA甲基化; 组蛋白修饰; MtMYBS1; 盐胁迫

收稿：2018-06-14   修定：2018-09-20

资助：山东省自然科学基金(ZR2015JL012)、国家自然科学基金(31300220和31501328)和中国博士后基金面上项目(2014M550366)。

Analyses of DNA methylation and histone modification of MtMYBS1 in Medicago truncatula under salinity stress

DONG Wei, LIU Xi-Jiang, GAO Tian-Xue, SONG Yu-Guang^*

School of Life Science, Qufu Normal University, Qufu, Shandong 273165, China

Corresponding author: SONG Yu-Guang; E-mail: SYG-0423@163.com

Abstract:

Epigenetic modifications, especially DNA methylation and histone modification, play important “switch” role in regulating gene expression. Previous studies have confirmed that Medicago truncatula Mt-MYBS1 was an essential functional gene involved in plant response to salinity stress. In this study, the expression, DNA methylation and histone modification of MtMYBS1 under salinity stress were analysed by reverse transcription PCR (RT-PCR), bisulfite sequencing PCR (BSP) and chromatin immunoprecipitation (ChIP). Following the up-regulated expression of MtMYBS1 under salinity stress, the DNA methylation of the promoter region and the 3′ terminal region gradually decreased, while the histone H3K9ac modification in the promoter region and the translation initiation site gradually increased. Further correlation analysis found that MtMYBS1 expression was negatively correlated with its DNA methylation modification, and positively correlated with histone H3K9ac modification under salinity stress. This study would provide critical theoretical guidance for further understanding of the expression and regulation of MtMYBS1 in the response to salinity stress in M. truncatula.

Key words: Medicago truncatula; DNA methylation; histone modification; MtMYBS1; salinity stress